臺灣高中英文教科書學術性字彙選用之分析研究

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(1)國立臺灣師範大學英語學系碩士論文 Master Thesis Graduate Institute Of English National Taiwan Normal University. 臺灣高中英文教科書學術性字彙選用之分析研究. A Study on Vocabulary Selection in Senior High School Textbooks in Taiwan from the Perspective of the Academic Word List. 指導教授: 葉錫南博士 Advisor: Dr. Hsi-nan Yeh. 研究生: 陳惠貞 Hui-chen, Chen. 中華民國一百零三年七月 July, 2014.

(2) 中文摘要本研究主要目的在於現行五個版本高中英語教科書中的學術性單字數量以及其分布進行分析比較，以期能瞭解現行高中英文教材在字彙學習方面如何協助學生發展其閱讀大學原文教科書之能力。學術性生字選用比較參照標準，乃以 Coxhead 學者於 2000 年所發表之學術用字詞彙表(the Academic Word List) 為主。同時，本研究亦找出未收錄於各版本之重要學術性詞彙，進而彙編成各版本相對應之補充字表，以供教師編製補充教材或學生進行自主學習使用。生字選用分析對象為目前市面上廣受採用之五個版本高中英文教科書(A、B、 C、D 及 E 版本)，共計三十冊。本研究分析之字彙聚焦於各版本基礎教材部分列於生字表之生字。所採用之研究分析工具為 Web VocaProfile Classic v.4 軟體,學術性單字詞彙量之分析單位為字族(word family)。本研究的主要發現如下: (一) 五套高中英文教科書中的學術性單字總量呈現顯著差異。C、D 及 E 三個版本含有 50%以上學術用字詞彙表之學術性生字，分別選用了 289 個，306 個以及 315 個學術性單字。A 及 B 兩版本含有 42%以及 45%學術用字詞彙表上的學術性生字，分別為 240 個及 256 個學術性單字。 (二) 從字頻角度來看各版本教科書學術性單字的選用時，各版本在高字頻學術性單字選用上並無顯著差異，但各版本在稍低字頻(less-frequent)學術性單字選用上呈現顯著差異。整體學術性單字總量的差異主要來自於稍低字頻學術性單字的選用。 (三) 各版本涵蓋最具學習價值來自最高字頻學術性單字字表(sublist 1)的數量及百分比分別為 D 版本(47 個，78%)、C 版本(45 個，75%)、A 版本(42 個， 70%)，B 版本(41 個，68%)以及 E 版本(41 個，68%)。而各版本前 180 個高字頻學術性單字的涵蓋數量及百分比則為 C 版本(124 個，69%)，D 版本 (118 個，66%)，A 版本(113 個，63%)，E 版本(111 個，62%)以及 B 版本(105 個，58%)。 (四) 至於學術性單字在各冊中的分布，學術性單字的數量並未如預期呈現隨冊數增加而不斷增加的趨勢，而是出現起伏的現象。大部分的版本在第四冊介紹最多的學術性單字，E 版本則是在高二上第三冊時，便呈現最大量的學術性單字。本研究結果，希望能提供教師更多關於現行高中教科書中字彙選用之概況，以便能為不同程度之學生選擇適切之教材。教科書編寫者亦能重新評估是否調整其學術性單字的選用。同時，也希望藉由補充字表之彙編來協助學生學習重要學術性單字，以協助其能早日發展出理解大學原文書之能力。. 關鍵字:字彙選用、學術性字彙、教科書分析 i.

(3) ABSTRACT This study aims to analyze and compare the sizes and distribution of academic words in the current five senior high school English textbook series following the 2010 Senior High School Curriculum Guidelines. The Academic Word List (Coxhead, 2000), acknowledged by experts to be beneficial in preparing students for higher education, is utilized as the reference point in this study. With the intent of assisting students to develop their academic vocabulary competence, this study also identified the academic words from the AWL being excluded from each textbook series to form complementary word lists which allow instructors to create supplementary teaching materials or serve as materials for students’ autonomous learning. Research data involves the vocabulary presented in the new word section in the five textbook series (A, B, C, D, & E). All of the vocabulary data in the textbooks were first lemmatized and then processed with lexical frequency analysis software, Web VocaProfile Classic v.4. The vocabulary data were then analyzed with the counting unit of “word family.” The major findings of this study are: 1. Significant differences were found in the sizes of academic words from the AWL among five textbook series. Three textbook series contains more than 50 percent of academic words from the AWL: textbook Series C with 315 word families, textbook series E with 306 word families and textbook series D with 289 word families. The A and B textbook series were found to include 42 percent and 45 percent of academic words from the AWL: textbook series B (256 word families) and textbook series A (240 word families). 2. In terms of distribution of academic words across sublists, statistical testing shows that the five textbook series do not differ in their strength in terms of selecting the most frequent academic words from the high-frequency academic word sublists (sublist 1 and the first three sublists). The differences of the amount of academic word selection among five textbook series mainly arise from the selection of academic words in the sublists which contain the less-frequent academic words (sublists 4-10). 3. The size and percentage of academic words selected from sublist 1 of the AWL in the five textbook series are as follows: 42 word families (70%) in textbook series A, 41 word families (68%) in textbook series B, 45 word families (75%) in textbook series C, 47word families (78%) in textbook series D and 41word families (68%) in textbook series E. The size and percentage of academic words selected from the first three sublists of the AWL are as follows: 105 word families (58%) in textbook series A, 113 word families (63%) in textbook series B, 124 ii.

(4) word families (69%) in textbook series D, 118word families (66%) in textbook series C and 111word families (62%) in textbook series E. 4. As for the distribution of academic words across six volumes, most of the textbook series contain the largest amount of academic words in the fourth volume except that SM has the largest amount of academic words in the third volume. Dramatic increase or decline patterns for the amount of academic words presented in advanced volumes were identified. Based on the findings, some pedagogical implications are provided for teachers, students and textbook writers. It is hoped that the results could facilitate students’ academic vocabulary development and provide teachers more information when selecting textbooks. Textbook writers could also re-evaluate their academic vocabulary selection in the new textbook series.. Keywords: vocabulary selection, academic vocabulary, textbook analysis. iii.

(5) ACKOWLEDGEMENTS This thesis project has finally been completed with guidance and support from many people. I feel indebted to all the professors, colleagues, classmates and family members that have provided guidance and support along the way and I would like to show my heartfelt gratitude to them. First and foremost, I would like to express my deepest gratitude to my advisor, Dr. Hsi-nan Yeh, who provided many insightful comments on this thesis project and discussed with me with great patience to tackle the challenges that I encountered during this process. There were also times when I felt overwhelmed by the data and could not see the end of this project. It was Dr. Yeh’s thought-provoking questions and encouragement that helped me get back on track and see the light. I am really grateful for his time and efforts put into my thesis project. Without his guidance and support, the completion of this thesis project would not have been possible. My sincere gratitude also goes to the honorable committee members, Dr. Vincent Chang and Dr. Howard Chen, who offered me valuable feedbacks to make the thesis more comprehensive. With their suggestions at the proposal hearing stage, this thesis project became more focused and manageable. With their advice at the oral defense stage, more factors were taken into consideration when interpreting the findings of this research. Their rich experience in research indeed enriches the perspectives of this study. My special thanks are also extended to Dr. Wen-ta, Tseng for his guidance and help with statistical analysis for this research. Without his assistance in statistics, the interpretation of the findings would not have been accomplished in time. I would also like to show my appreciation to my colleagues in Shi-Lin High School of Commerce for their encouragement: Carolyn Li, Kun-long Liu, Anne Tseng, iv.

(6) Maggie Chang, Chih-yu Liao, Shi-yuan Gong, Ping-yuen Zhao, Shi-chi Chou, Shu-zhen Lin, and Mei-feng Chang. It is indeed challenging to manage the roles of being an in-service teacher and a graduate student at the same time. Their encouragement and experience sharing help me gain the balance between work and study. I also want to thank all the classmates in the TESOL program of NTNU for companionship. Days that we spent in tackling issues of conducting research and showing support for each other would be remembered. I would especially like to thank Kendra Chou for words of encouragement and support in many ways in the process of doing this thesis project. Last but not the least, I owe my greatest gratitude to my beloved family—my parents and sister, Amy. It is their love, support, and understanding that gave me the courage and strength to walk through this intellectual journey. This thesis is especially dedicated to them.. v.

(7) TABLE OF CONTENTS CHINESE ABSTRACT………………………………………………………………i ENGLISH ABSTRACT……………………………………………………………...ii ACKNOWLEDGEMENTS………………………………………………………...iv LIST OF TABLES…………………………………………………………………..ix LIST OF FIGUES………………………………………………………………….x CHAPTER ONE INTRODUCTION………………………………………………..1 Background and Motivation of the Study………………………………………..1 Purpose of the Study………………………………………………………………3 Research Questions………………………………………………………………..4 Significance of the Study…………………………………………………….…….5 Definition of Terms………………………………………………………………...6 CHAPTER TWO LITERATURE REVIEW……………………………………...10 The Importance of Vocabulary………………………………………………….10 Learners’ Vocabulary Size and Lexical Thresholds……………………………11 Lexical Thresholds for L2 Reading Comprehension…………………………...12 Suggested Vocabulary Size for L2Learners from Lexical Threshold Studies….13 Vocabulary size for English for Academic Purposes……………………………16 Vocabulary Selection……………………………………………………………..17 General Principles for Vocabulary Selection……………………………………17 Vocabulary Selection for Learners in Preparation for Academic Study………..19 High-frequency Words and General Service List…..……………………..……...19 Academic Words and Academic Word List…………………………….……..21 Vocabulary in Textbooks……………………………………………………….24 Suggested Number of New Words…………………………………………….25 Suggested Sequence of Vocabulary Items……………………………………..26 The Evaluation Criteria for Textbook Vocabulary…………………………….27 Vocabulary in Senior High School English Textbooks in Taiwan……………28 Specifications on Vocabulary for Senior High School Textbooks in Taiwan….29 Recent Vocabulary Studies on Senior High School English Textbooks……….30 vi.

(8) CHAPTER THREE METHOD……………………………………………………34 Data Collection……………………………………………………………..…...34 The Selected Senior High School Textbooks for Analysis………………….....34 Instruments…………………………………………………………………….38 Procedures and Data Analysis………………………………………………...39 CHAPTER FOUR RESULTS AND DISCUSSIONS …………………………….42 Sizes of Academic Vocabulary in Textbooks………………………..…………42 Distribution of Academic Vocabulary in Textbooks…………………..………47 Distribution of Academic Vocabulary across Sublists in Textbooks……………47 Distribution of Academic Vocabulary across Six Volumes in Textbooks………53 Complementary Word Lists……………..……………………………………..57 Frequency Scheme Analysis of New Words in Textbooks…………………....62 Sizes and Distribution of New Words on Frequency Scheme (GSL+AWL) in Textbooks……………………………………………………………………….63 Sizes and Distribution of High Frequency Words from the GSL in Textbooks ………………………………………………………………………65 Distinct Vocabulary Selection Features of Textbook Series……………………68 Frequency Scheme Analysis of New Words Introduced through the Curriculum………………………………..………………………………….....73 Sizes of New Words on Frequency Scheme (GSL+AWL) through the Curriculum…………………………………………………………………….74 CHAPTER FIVE CONCLUSIONS ……………………………………………..77 Major Findings………………………………………………………………….77 Academic Vocabulary Size………………………………………………….....77 Academic Vocabulary Distribution…………………………………………....78 Complementary Word Lists…………………………………………………...79 Frequency Scheme Analysis of New Words in Textbooks…………………….80 Frequency Scheme Analysis of New Words Introduced through the Curriculum……………………………………………………………………..81 Pedagogical Implications…………………………………………………..…...81 Limitations of Research……………………………………………………..….85 vii.

(9) Suggestions for Future Research…………………………..…………………..86 REFERENCES……………………………………………………………………...89 APPENDIX APPENDIX APPENDIX APPENDIX APPENDIX APPENDIX. A………………………………………………………………………103 B………………………………………………………………………105 C………………………………………………………………………109 D………………………………………………………………………116 E………………………………………………………………………123 F………………………………………………………………………129. APPENDIX G………………………………………………………………………134. viii.

(10) LIST OF TABLES Table 1 The Size of Lessons of the Basic Learning Materials in Each Textbook Series…………………………………………………………………………………..36 Table 2 The Size of Lessons with Vocabulary Marked for Advanced Learning Materials in Each Textbook Series………………………………………..……….36 Table 3 Chi-square Test for the Amounts of Academic Words across Five Textbook Series…………………………………………………………………………………..43 Table 4 Chi-square Test for the Amounts of Academic Words in Five Textbook Series Plus 1200-word List…………………………………………………………………46 Table 5 Text Coverage of Each Sublists of the AWL……………………………………..48 Table 6 Chi-square Test for the Amounts of Academic Words from Sublist 1 across Five Textbook Series………………………………………………………………...50 Table 7 Chi-square Test for the Amounts of Academic Words from the First Three Sublists across Five Textbook Series………………………………………………51 Table 8 Chi-square Test for the Amount of Academic Words from Sublist 4 to Sublist 10 across Five Textbook Series…………………………………………………….52 Table 9 The 84 Academic Words not Selected in any of the Textbook Series…………59 Table 10 The Amount of Academic Words on Each Level of the CEEC Six-level Word List…………………………………………………………………………..61 Table 11The 44 Academic Words not Selected in the CEEC Six-level Word List….....62 Table 12 Sizes and Percentage of New Words on the GSL and the AWL Frequency Scheme among Textbook Series…………………………………………………..64 Table 13 Chi-square Test for the Amount of New Words on the GSL and the AWL across Five Textbook Series……………………………………………………….64 Table 14 Chi-square Test for the Amounts of New Words from the GSL across Five Textbook Series…………………………………………………………………….66 Table 15 Chi-square Test for the Amount of New Words on the first 1,000 words of the GSL across Five Textbook Series…………………………………………………66 Table 16 Chi-square Test for the Amounts of New Words on the second 1,000 words of the GSL across Five Textbook Series…………………………………………….68 Table 17 Chi-square Test for the Amounts of New Words in Lemmas on the Less-frequent Word Category across Five Textbook Series…………………..73 Table 18 Sizes and Percentage of New Words on the GSL and the AWL Frequency Scheme through K-12 Curriculum………………………………………………..74 Table 19 Chi-square Test for the Amount of New Words on GSL and AWL in 1200-Word List and Textbook Series……………………………………………..75 ix.

(11) LIST OF FIGURES Figure 1. Line graph showing academic word distribution across ten sublists in five textbook series……………………………………………………………..49 Figure 2. Line graph showing academic word distribution across six volumes in five textbook series……………………………………………………………..55 Figure 3. Bar chart showing the amounts and distribution of new words selected from the GSL K1, K2 and the AWL frequency scheme among five textbook series……………………………………………………………………….70. x.

(12) CHAPTER ONE INTRODUCTION Chapter one presents the background, motivation, purpose, and significance of this study. Research questions and definitions of terms are also provided for an overview of the present study. Background and Motivation of the Study Based on my teaching experience and interaction with students, reading textbooks in English seems to be a great challenge to many college students in Taiwan. Several of my former students mentioned the difficulties in reading English-medium textbooks in colleges and their constant needs of looking up unfamiliar words in the dictionaries in order to comprehend their reading assignments. Occasionally, students also requested me for help with their reading assignments in English texts. The requirements of reading English-medium textbooks in colleges do not just happen to my own students. It is, in fact, a prevalent phenomenon in the higher education setting in Taiwan. Earlier studies reveal that English-medium textbooks are frequently adopted in the higher education settings in Taiwan (Kong, 1996; Lin & Kong, 2000; Chen, et al., 2002). To be more specific, eighty percent of 72 instructors from National Taichung University of Science and Technology and Ming Chuan University participating in a survey were reported to use English-medium textbooks for specialized knowledge instructions (Kong, 1996). In the same study, up to 75% of the instructors in National Taiwan Universities of Science and Technology also stated that they utilized English-medium textbooks in class. More recently, Yu and Cheng (2010) surveyed 1,000 instructors and 1,000 students across 40 universities and colleges in Taiwan to explore textbook selection and use behaviors with investigation of the language of the textbooks included. About 63% of the instructors reported that 1.

(13) English-medium textbooks were adopted for teaching. Similarly, about 63% of the college students reported that they used English-medium textbooks in class. Hsu (2011) also acknowledged the common practice of using English-medium textbooks in higher education setting in Taiwan. With the statistical data released by the MOE (2013) on the percentage of senior high school graduates choosing to attend colleges averaging around 95% over the past five years, it is reasonable to argue that the majority of high school graduates need to read English for academic purposes when they pursue further studies in higher education settings in Taiwan. The reading challenge that my students faced has also been a concern for many other college students in Taiwan. Huang (2004) conducted a research on college students’ vocabulary knowledge, content knowledge, and their reading comprehension. Despite the rich knowledge in content area, 246 non-English major college students in Taiwan still found it difficult to read academic texts in English due to lack of vocabulary knowledge in academic words. More recently, the study of Tsou and Huang (2013) also suggested a gap between senior high school graduates’ perceptive vocabulary knowledge and the required vocabulary threshold for adequate reading comprehension expected by instructors in the higher education setting. My students’ learning experience and the related studies shown above prompted my curiosity to investigate whether the vocabulary students have learned in high school English classes would fully prepare them for reading English-medium college textbooks. One way to investigate this issue is to examine the vocabulary selection in the English textbooks of senior high school with the academic words on the Academic Word List (Coxhead, 2000) since the Academic Word List (AWL) is developed with the purpose of preparing students for higher education. Nation (2001) promotes the study of academic words on the AWL for students in the English for Academic 2.

(14) Purpose (EAP) track. Decarrico (2001) also reckons the importance of the Academic Word List (AWL) for academic English and suggests that students with the goal of university study need to learn the academic words on the AWL. By the beginning of 2013, the new English textbook series following the 2010 curriculum guidelines for senior high school had just had their full volumes. In February 2013, the four major senior high English textbook publishing companies in Taiwan published their last volume, Book Six, of their latest senior high textbook series, which follow the 2010 curriculum guidelines. Therefore, it is also timely to examine the latest senior high school English textbook series in hope of shedding light on the selection of the language learning components in the current textbook series. Purpose of the Study This study aims to provide some objective and empirical evidence of vocabulary selection in the five1 major senior high school English textbook series to high school teachers so that they can be better-informed about the vocabulary selection in each of the textbook series. In addition, this study also attempt to identify the academic words from the Academic Word List (AWL) that are not selected in each textbook series and compile these words to form some supplementary word lists complementary to each textbook series. These word lists could be utilized by senior high school teachers or instructors of English at the college level to develop teaching or learning materials for their students whose learning needs center around English for Academic Purposes (EAP). The compilation of the supplementary word lists also echoes the principle of differentiated instruction in the latest 12-year compulsory 1. The Far East Book Company, Lung Teng Cultural Company, Nan I Enterprise Company, and San Min Book Company are the four publishers for senior high school English textbooks in Taiwan. Most publishers released one textbook series while the Far East Book Company published two textbook series: Chen et al.’s (2010-2013 edition) Far East English Reader for Senior High Schools (FEC) and Shih et al.’s (2010-2013 edition) Far East English Reader for Senior High Schools (FES). 3.

(15) education reform as the students who have fulfilled the basic vocabulary learning requirements will be able to further utilize the supplementary lists of words at a more advanced level, the academic vocabulary. Research Questions The 2010 curriculum guidelines for senior high school state that the objective of senior high school English curriculum aims to cultivate students’ English competences to prepare the students for higher education or employment (MOE, 2009). As mentioned earlier, the recent government report (MOE, 2013) shows that about 95% of senior high school students choose to pursue higher education over the past five years in Taiwan. It is worth the effort examining to what extent the senior high school English curriculum has prepared students for further studies in colleges. More specifically, this study will analyze vocabulary selection in the five textbook series with the Academic Word List developed by Coxhead (2000). The Academic Word List, developed primarily to prepare learners for higher education, contains 570 word families that are most frequently encountered in academic texts. The 570 word families are divided into ten sublists based on the frequency of occurrence. The more frequent the words are on the AWL, the more likely the words would appear in the academic texts. Coxhead (2000) suggested that the academic words on the first three sublists occur with relatively high frequency and have the greatest value for learning. According to Coxhead (2000), the academic words from the 60 word families on Sublist 1 occur more frequently than any other academic words on other sublists. In fact, the academic words from the 60 word families on Sublist 1 accounts for about one third of the total coverage of the whole word list while the ones from Sublist 2 only provides half of the coverage of the first 60 word families on Sublist 1. Therefore, this study will adopt the Academic Word List to analyze vocabulary selection in the. 4.

(16) five textbook series in terms of sizes, distribution across ten sublists and with a special focus on academic words falling on Sublist 1 and the first three sublists. With the above-mentioned purposes of study and features of word lists, the research questions of this study are listed as follows: 1. What is the size and distribution of academic words from the Academic Word List (AWL) in each of the high school English textbook series? Are there significant differences among them? 2. What is the percentage of academic words from AWL Sublist 1 in each of the senior high school textbook series? What are these academic words? 3. What is the percentage of academic words from AWL Sublist 1 to Sublist 3 in each of the five senior high school textbook series? What are these academic words? Significance of the Study This study aims to examine the vocabulary selection among the five latest senior high school English textbook series in Taiwan from the perspectives of the Academic Word List. Sizes and distribution of academic words are revealed. Supplementary word lists for each textbook series are compiled. Previous vocabulary selection researches of senior high school English textbooks in Taiwan examined mostly two textbook series or six textbook series with a focus on one particular volume (Chang, 2002; Fan, 2004; Huang, 2008; Lin, 2006). The number of volumes for analysis often ranges from six to twelve. The present study attempts to provide a more comprehensive and thorough picture of vocabulary selection of all the current senior high school English textbook series. With the findings from empirical data from thirty volumes of textbooks, senior high school teachers can make better-informed decisions in textbook selection. Instructors in the higher education. 5.

(17) setting can also develop a better understanding of how well the high school graduates might have been equipped with the academic words for university study. High school textbook writers can also benefit from the systematic examination of the vocabulary selection in each textbook series and take the findings into consideration when engaged in future textbook development projects. The curriculum guidelines for the 12-year compulsory education are expected to be announced to the public in early 2016 when the next new senior high school textbook writing projects will also be initiated (MOE, 2013). The findings of this study can provide textbook writers an opportunity for reflections and incorporation of corpus-based vocabulary selection analysis for new textbook series. In addition, the supplementary word lists for each textbook series can serve as useful materials for students who need to focus on English for Academic Purposes (EAP) and for instructors who plan to assist their students to further develop their academic vocabulary. High school teachers can use the supplementary word lists for differentiated instruction while instructors at higher education can design a more efficient lexical syllabus for their students on the EAP track. Definition of Terms As this study involves quantitative measure of vocabulary and different units of measuring vocabulary would lead to different results, it is important to state the measuring units used in conducting this vocabulary selection research. 1. Tokens, types and lemmas: Tokens refer to the number of running words in a text while types are the number of different words (Nation, 2001; Read, 2000; Schmitt, 2010). The example sentence, “Fat cats eat fat rats”, consists of five tokens. Yet, it contains only four types as the two occurrences of the token fat belong to the same type. Tokens are. 6.

(18) sometimes called running words (Nation, 2001) while types are termed as word forms, also considered to be the basic psycholinguistic element (Schmitt, 2010). A lemma, on the other hand, is comprised of a base form of a word and only the most frequent and regular inflections (Milton, 2010; Nation, 2001; Schmitt, 2010). In English, a lemma would include regular plurals and possessives in nouns, regular inflections –s, -ed, -ing and –en past participles forms in verbs, and comparative and superlative –er and –est endings in adjectives (Bauer & Nation, 1993; Milton, 2010). The items included under a lemma usually belong to the same part of speech (Francis & Kucera, 1982). Therefore, if the textbook presents usages of the vocabulary item “result” as a noun and as a verb in the wordlist section, vocabulary load of this scenario would be counted as two lemmas. The use of lemmas as the counting unit for words manifested the idea of learning burden (Swenson & West, 1934, as cited in Nation, 2001:7). Types could be an ideal measuring unit of vocabulary acquisition for learners at beginner level as each new word form could be a completely new word to them. Accordingly, types are often adopted as a measuring unit for textbook vocabulary input research, especially for the textbooks catering for the beginner level and featuring on reading text analysis (Alsaif & Milton, 2012; Konstantakis & Alexiou, 2012). As learners gradually develop their knowledge of the inflectional system of English, lemmas could be used to capture learners’ vocabulary growth or knowledge. For example, vocabulary size tests such as Vocabulary Level Test (Nation, 1990& 2001) and XLex (Meara & Milton, 2003) draw on lexical frequency information where lemmatized word counts are employed. Lemmas can be an ideal measuring unit of vocabulary knowledge for senior high school students in Taiwan as most students have learned and are familiar with the most frequent and regular inflectional rules of English in junior high school. In addition, Schmitt (2010) also 7.

(19) proposes lemmas as a reasonable compromise for measuring both receptive and productive vocabulary use. This study, an examination of textbook vocabulary selection with the Academic Word List, utilized lemmas to be the basic quantifying unit for vocabulary data compilation from the textbooks as it could aid in revealing the size of the less-frequent words in the textbooks and to provide an overall picture of vocabulary selection in textbooks. 2. Word families A word family consists of word forms that are semantically related (Schmitt, 2010). A word family is made up of a base word, its inflected forms and some closely related derived forms (Bauer & Nation, 1993). Take the headword “approach” for example. The word family of “approach” includes the following six word forms: “approach”, “approached”, “approaches”, “approaching”, “approachable”, and “unapproachable.” As the Academic Word List is organized by word families, this study adopted “word families” as a main measuring unit to show the proportion of the academic words in textbooks against the 570-word-family AWL. 3. Vocabulary items or lexical items: “Vocabulary items” or “lexical items” are often used by vocabulary specialists or researchers to refer to words or vocabulary when a specific measuring unit is not assigned to them. For example, Schmitt (2011) utilized the term of “lexical items” frequently and extensively to talk about second language vocabulary acquisition and how to do research on vocabulary: “…Vocabulary acquisition is incremental both in terms of acquiring an adequate vocabulary size and in terms of mastering individual lexical items….” Read (2000) used “what does it mean to know a lexical item” when introducing the concept of vocabulary knowledge. Coxhead (2000) used the terms “lexical item” and “vocabulary item” interchangeably in the article that introduced the Academic 8.

(20) Word List: “ …Instead, ,the AWL might be used to set vocabulary goal for EAP courses, construct relevant teaching materials, and help students focus on useful vocabulary items.” This study used the term “vocabulary items” or “lexical items” in the same way as most researchers do when necessary.. 9.

(21) CHAPTER TWO LITERATURE REVIEW The review of literature in chapter two centers around issues of vocabulary and textbook related to this study. It starts with the examination of the importance of vocabulary for second language learning, and then proceeds to explore second language (L2) learners’ vocabulary size from the perspective of lexical threshold for L2 reading comprehension, specifically targeting on reading academic texts. The review of vocabulary selection literature subsequently follows with discussions on vocabulary selection principles for English for General Purposes (EGP) as well as English for Academic Purposes (EAP). Concepts and word lists used for discussion on vocabulary selection, such as high-frequency words, academic vocabulary, General Service List (GSL), Academic Word List (AWL), are also introduced along with vocabulary selection literatures. The next part targets on the vocabulary in textbooks, with literature review of suggested arrangement and evaluation criteria for vocabulary in textbooks. The final part of literature review focuses on vocabulary in senior high school textbooks in the context of Taiwan. Related studies on vocabulary selection in the senior high school textbooks in Taiwan were also elaborated. The Importance of Vocabulary Vocabulary is an important component of for both language use and language learning. Linguist David Wilkins (1972) stated that “…while without grammar very little can be conveyed, without vocabulary nothing can be conveyed…” (p.111). Laufer (1986) shared the same view and suggested that “without adequate lexis, there is no proper language competence or performance.” Nation (1990) also pointed out that inadequate vocabulary knowledge had resulted in many difficulties for L2 students’ both receptive and productive language use. Read (2000) indicated that 10.

(22) vocabulary knowledge is “a prerequisite for effective language use.” Vocabulary knowledge has been recognized as a good predictor of reading comprehension (Laufer, 1992; Nation, 2001& 2006; Qian, 1999 & 2002). Numerous researches have also provided empirical data and demonstrated the importance of vocabulary in language learning by showing high correlations between vocabulary knowledge and various measures of language proficiency (Albrechtsen, et al, 2008, Alderson, 2005; Laufer, 1992). Vocabulary size of L2 students in Israel was found to correlate with reading comprehension at .50-.70 (Laufer, 1992). More recently, Albrechtsen, Haastrup and Henriksen (2008) also revealed a high correlation of .73-.80 between L2 vocabulary size of Danish students and their L2 reading ability. Alderson (2005) explored the relationship between vocabulary knowledge and language proficiency systematically in the DIALANG, a diagnostic test development project. Two vocabulary tests showed that vocabulary knowledge correlated with reading at .64, listening at .61-.65, writing at .70-.79 and grammar at .64. Vocabulary is proved to have a strong relationship with various language skills. The importance of vocabulary can be concluded by statement of Alderson (2005) that “the size of one’s vocabulary is relevant to one’s performance on any language tests. In other words, language ability is to quite a large extent a function of vocabulary size.” Since vocabulary knowledge or size plays such an important role in language learning, the questions that concerns most ESL/EFL teachers related to vocabulary learning would be: how many words does a learner need to know and what are the words that should be learn first? Learners’ Vocabulary Size and Lexical Thresholds The amount of words that learners should learn depends to a great extent on learners’ needs. Based on the logic of a communicative approach to vocabulary ability,. 11.

(23) the discussion of vocabulary size of L2 learners would not be in an absolute sense, but in relation to particular contexts of use (Chappelle, 1994). For example, the questions raised would be how many words L2 learners need to know in order to read authentic novels or to read college textbooks in English. Since one of the objectives of the 2010 curriculum guidelines for senior high school in Taiwan is to cultivate students’ competence for higher education (MOE, 2009), and from recent surveys, the majority of university students in Taiwan need to read English-medium textbooks (Chen, et al., 2002; Lin & Kong, 2000; Yu & Zheng, 2010), the vocabulary size that senior high school students should develop could be examined through the concept of “lexical threshold,” the minimal vocabulary knowledge necessary for “adequate” reading comprehension (Alderson, 1984; Laufer, 1992 & 2010; Nation, 2006). Lexical Thresholds for L2 Reading Comprehension Reading in a foreign language involves not only content knowledge and reading skills as readers in L1 do but also L2 linguistic knowledge, which consists of both syntactic and lexical knowledge (Alderson, 1984; Laufer, 2010). Alderson (1984) raised the insightful question of reading in a foreign language: Is reading in a foreign language a reading problem or a language problem? To respond to the question, Alderson (1984) proposed “language threshold hypothesis,” which suggested L2 learners need to possess a certain amount of linguistic knowledge in order to function well in L2 tasks, such as reading or listening. With multiple regression analysis, Bosser (1991) showed that L2 linguistic knowledge level predicted L2 reading abilities four times better than L1 reading abilities except for learners at advanced level group. As for which component of linguistic knowledge playing a much more significant role for reading in a foreign language, lexical knowledge was found to contribute more to L2 academic reading success than syntactic knowledge. 12.

(24) (Saville-Troike, 1984; Laufer& Sim, 1985). Most of the researches exploring language threshold for reading comprehension have focused more on lexical knowledge instead of syntactic knowledge. Findings from lexical knowledge for reading comprehension studies on lexical threshold are useful for second or foreign language education because teachers and course designers can set up the vocabulary learning goals or design lexical syllabi accordingly. Suggested Vocabulary Size for L2Learners from Lexical Threshold Studies Ever since Alderson’s (1984) call for investigation of “language thresholds” for L2 reading comprehension, several studies have been conducted to explore pedagogically usable thresholds (Laufer, 1989, 1992 & 2010; Laufer & Sim, 1985; Hsu, 2011; Hu & Nation, 2000; Nation, 2001& 2006). Opinions and findings of these lexical thresholds vary as a result of different operationalized definitions of what it means to be “adequate” L2 reading comprehension and research approaches. Different levels of reading comprehension might be required in different contexts, and subsequently result in different lexical thresholds. As for research approaches, the search for lexical thresholds for reading comprehension often proceeds in two complementary approaches: one is to examine the coverage that words of different frequency level provide to the texts; the other is to test learners on text comprehension and relate different reading scores to learners’ vocabulary size (Cobb & Horst, 2001 a). In other words, the first approach places emphasis on the reading texts and the lexical coverage of the reading texts while the second approach involves the reader and search for the size of the readers’ sight vocabulary. Sight vocabulary refers to the words that learners are so familiar that they can be recognized and decoded immediately without much cognitive effort when learners engage in a reading task (Laufer, 2010). The larger the size of sight vocabulary of a learner, the more lexical. 13.

(25) coverage he or she has for the reading texts. The more lexical coverage the learner has for a text, the higher chances for the learner to have better reading comprehension of the text. To tackle the issue of learners’ vocabulary size for adequate comprehension, Laufer (1989) first investigated lexical coverage of academic texts for “adequate” reading comprehension, in which a score of 55% was set as the operationalized definition for “adequate” comprehension. The results showed that the learner group that scored 95% and above on lexical coverage had a significantly higher number of successful readers (scoring at least 55% or above on reading comprehension test) when compared to the 90% - 94% group. Some learners at different coverage level still received passing scores for their reading comprehension. This made Laufer (1989) conclude that the 95% text coverage is a lexical threshold of probabilistic nature. “Adequate” comprehension might happen when students possess a vocabulary size lower than 95% of lexical coverage of texts, but the chance or probability is low. Using two comprehension tests and adopting the score that most learners in the 100% coverage group receives as the passing score for “adequate” comprehension (scoring 87.5%), Hu and Nation (2000) searched the lexical coverage for “adequate” reading comprehension on fiction texts. Four different lexical coverage groups (80%, 90%, 95%, and 100%) were created by replacing some words in the text with non-words. Results showed that none of the students could reach “adequate” comprehension at 80% of coverage while some students could at the 90% and 95% coverage groups. Ninety-eight percent of lexical coverage of text is concluded to be the probabilistic threshold for reading fiction texts adequately while 80% lexical coverage of text is believed to be the all-or-nothing threshold. The two different lexical coverage suggestions vary due to different definition of “adequate” comprehension yet both 95% and 98% lexical coverage 14.

(26) suggestions are acknowledged depending on what level of “adequate” comprehension is expected. In terms of lexical coverage of text for “adequate” reading comprehension, it can be concluded by Nation’s (2001) statement that “The probabilistic threshold is 98%. With this coverage, almost all learners have a chance of gaining adequate comprehension. If, instead of adequate comprehension, a standard of minimally acceptable comprehension is applied (as Laufer did in her study), then 95% coverage is likely to be the probabilistic threshold” (p. 147). The lexical coverage of texts for “adequate” comprehension was identified, and the investigations on size of sight vocabulary for “adequate” comprehension followed subsequently from the two complimentary research approaches. To locate the threshold vocabulary level, Laufer (1992) took the reader approach in which the reading comprehension scores and the university students’ vocabulary size were examined. With “adequate” comprehension score set at 56%, 3,000 word-family level was found to be the lexical threshold where there are more readers than non-readers. With “adequate” comprehension score at 63%, the vocabulary knowledge of 4,000 word families was needed while the vocabulary knowledge of 5,000 word families would be required for “adequate” comprehension score set at 70%. The vocabulary knowledge of 3,000 word families is concluded to be the minimal requirement for reading unsimplified texts. The findings of this study offered practical implications for syllabus designers to set vocabulary learning goals. On the other hand, Hirsh and Nation (2001) adopted the text coverage approach in which they used General Service List (West, 1957) for the first 2,000 word families and the old Thorndike and Lorge’s teacher’s word list (1944) for words beyond 2,000 word families to analyze the lexical coverage of unsimplified teenager novels. To reach the 97%-98% text coverage for “adequate” reading, the vocabulary size needed is suggested to be 5,000 word families. With the intent of more accurate estimates for the number of word families that 15.

(27) learners need for “adequate” comprehension with various genres of texts, Nation (2006) developed word family lists from British National Corpus (BNC) frequency list (Leech, et al., 2001) and searched for more precise vocabulary size that learners need to comprehend different genres of texts. The findings revealed that 3,000 word families and proper nouns would give 95% coverage of the spoken texts. To get 98% coverage for spoken texts, learners need to have a vocabulary size of 6,000-7,000 word families and the knowledge of proper nouns, which often accounts for about 4%-5% of text coverage. For written texts of newspapers or novels, learners need 3,000 word families and the knowledge of proper nouns to reach 95% of text coverage. However, to reach the 98% text coverage of written texts, learners would need a vocabulary size of 8,000-9,000 word families and the knowledge of proper nouns as required in Laufer (1989) and Hu and Nation (2000). The two lines of lexical threshold investigations seem to find similar results when adopting the 95% text coverage as the probabilistic threshold despite different genres of written texts (Laufer focused mainly on academic texts while Nation aimed more at novels and newspapers): L2 learners need to have the vocabulary size of 3,000 word families and proper nouns to reach 95% of text coverage for “adequate” reading comprehension. The lexical threshold of 3,000 word families has been acknowledged and recommended by many researchers (Cobb & Horst, 2001a; Nation, 2000; Nation & Waring, 1997; Thornbury, 2002) to be an important vocabulary learning goals for L2 learners in order to provide initial access to authentic texts. Vocabulary size for English for Academic Purposes For L2 learners in the senior high school in Taiwan in preparation for university study, what concerns the instructors, textbook writers and syllabus designers more would be the lexical threshold for reading academic texts. Laufer. 16.

(28) (2010) re-examined the lexical threshold for academic English with more rigorous research design and suggested two thresholds for reading academic texts in English: the optimum one, (vocabulary knowledge of 8,000 word families plus knowledge of proper nouns resulting in the 98% text coverage) and the minimal one (vocabulary knowledge of 4,000-5,000 word families and knowledge of proper nouns leading to the 95% coverage of texts). Using BNC frequency word list, Hsu (2011) investigated the vocabulary threshold of English-medium textbooks and research articles in the field of Business for EFL learners. Business textbooks were discovered to reach 98% text coverage at the 5,000 word-family level and to get to 95% text coverage at the 3,500 word-family level. Research articles in business discipline requires the vocabulary knowledge of 8,000 word families to provide a 98% text coverage and 5,000 word families to supply 98% coverage of texts. The results from these two lexical threshold studies for “adequate” comprehension of academic texts offer rich information for L2 learners and instructors to set up the vocabulary learning goals for academic studies. Vocabulary Selection While 3,000 word families are generally agreed to be a reasonable goal for L2 learners on the English for general purpose track and students in preparation for university studies should aim at around 3,500-8,000 word families depending on the language demands of different disciplines, L2 instructors, syllabus planners and students would have to deal with another important issue in vocabulary learning planning, that is, which 3,000 word families should be learned or what words should be learned first. This is the issue of vocabulary selection (Richards, 2001). General Principles for Vocabulary Selection The investigation of the issue of vocabulary selection can be traced back to 17.

(29) early works of Faucett, et al. (1936), Ogden (1930), Thorndike and Lorge (1940), and West (1957). Frequency of words counted from a large collection of texts plays an important role in the early works of vocabulary selection at the first half of the twentieth century (Richards, 1974 & 2001). Early lexicometrics specialists propose that word frequency counts offer the basis for a more scientific and objective approach to vocabulary selection (Richards, 1974). This “frequency” principle is still acknowledged by numerous researchers of these days as an important criterion for vocabulary selection (Coady, et al., 1993; Cobb, 2013; Gairns & Redman, 1986; Geothals, 2004; Nation, 2001& 2003; Nation & Waring, 1997; Richards, 1974 & 2001; Schmitt, 2000; Schmitt & Schmitt, 2012; Sinclair & Renouf, 1998). Word frequency refers to “how often the word occurs in normal use of the language” (Nation & Waring, 1997). High-frequency words tend to give a much greater return in opportunities for language use than low-frequency words do (Nation, 2003). Frequency of a word can be an indicator of its usefulness (Goethals, 2004; Nation & Waring, 1997) and its difficulty (Ryder & Hughes, 1985). Thus, the frequency of words is often regarded as an important criterion for vocabulary selection. Word frequency count is acknowledged to be an essential component in planning word lists for language teaching yet, to ensure the usefulness of the selected words, the high-frequency words also have to occur across a wide range of different texts. “Range” of the words also plays an important role in the process of vocabulary selection. The selection of “range” would be determined based on learners’ needs and learning goals. For students with learning English for general purposes, words appearing across a wide range of texts would be selected while learners of English of specific purposes, words from specific fields would be selected. Students’ needs and proficiency level are also recognized as important criteria for vocabulary selection in a course or curriculum (Allen, 1983; Gairns & Redman, 1986). When taking students’ 18.

(30) needs and background into consideration, cultural factors should also be taken into consideration in the process of vocabulary selection as learners might have special cultural interests in L2 that might be distinct from native speakers (Gairns & Redman, 1986). In addition to the four criteria mentioned above, Richards (2001) also points out five other criteria that are useful for vocabulary selection: (1) teachability: concrete vocabulary can be easily illustrated through pictures or by demonstration, (2) similarity: word items similar to words in learners’ native language, (3) availability: less-frequent words yet are readily available when certain topics are presented, (4) coverage: words that cover the meaning of other words, and (5) defining power: words that are useful in defining other words. The act of vocabulary selection would involve different criteria depending on the objectives of the language curriculum or programs or the purposes of the wordlists. Vocabulary Selection for Learners in Preparation for Academic Study Allen (1983) pointed out that learners’ needs should be the most important criteria for selecting words. For L2 learners in preparation for academic study, such as the senior high school students in Taiwan, several researchers and vocabulary specialists (Cobb & Horst, 2001a; Decarrico, 2001; Nation, 2001& 2003; Paquot, 2011; Schmitt, 2010; Thornbury, 2002) have recommended that L2 learners should be first equipped with a core vocabulary of 2,000 high-frequency words, then with study of academic words for higher education study. High-frequency Words and General Service List Nation (2001) categorized English vocabulary into four groups: high-frequency words, academic words, technical words, and low-frequency words. High-frequency words, also known as core words, or basic words (Paquot, 2010), provide a large amount of text coverage of both spoken and written texts and occur 19.

(31) highly frequently in all kinds of language uses. The best-known list of high-frequency words is the West’s (1953) General Service List of English Words (GSL), which is created from a five-million word corpus of written texts and contains about 2,000 headwords considered suitable for foreign language teaching (Decarrico, 2001; Nation, 2001; Richards, 2001). The list was created with the incorporation of findings from a major vocabulary selection study of that time: The Interim Report on Vocabulary Selection (Faucett, Palmer, West, and Thorndike, 1936). The criteria for GSL compilation include: word frequency, structural value, universality, subject range, definition words, word-building capacity and style (Howatt, 2004). Information on frequency of different meanings of each word is also available to teachers. GSL has been quite useful in second or foreign language education as it provides a reference in making decisions about what words to use in L2 learning materials: course books and graded readers and which meaning of the words to be taught first. GSL also claims to provide about 80% coverage of most written texts, and thus become quite influential on L2 learning (Carter & McCarthy, 1988). On the other hand, GSL has also received some critiques, mainly on its out-datedness, lack of spoken data, utility, and availability (Richards, 1974 & 2001; Carter & McCarthy, 1998). Despite several disadvantages mentioned, GSL has continued to be useful as Nation and Hwang (1995) demonstrated quite large overlap between more recent frequency count and GSL. The GSL used in the study was a re-organized version of GSL, in which the original GSL was arranged in frequency order and concept of word families. Based on Nation and Bauer’s (1995) criteria of determining word families, the re-organized GSL contains 1,965 word families and has been adopted for numerous lexical profiling and vocabulary selection studies (Coxhead, 1998 & 2000; Fan, 2004; Horst, 2005; Nation & Hwang, 1995; Nation & Wang, 1999). Nation and Hwang (1995) discovered that replacing some words in GSL with some other words in the top 2000 frequency band 20.

(32) only resulted in 1% coverage difference. The first 1,000 words of GSL was also found to provide about 77% of text coverage while the second 1,000 words offer about 5% in academic texts in Nation and Hwang’s study. The finding was consistent with the earlier GSL claim of about the 80% text coverage that it could offer. The high-frequency words of about 2,000 word families are proven to be an essential part of vocabulary selection for L2 learners heading toward academic study. Academic Words and Academic Word List High-frequency words are indeed an important part of vocabulary selection for L2 students preparing for academic study. However, the lexical coverage of high-frequency words in academic texts often just average around 80%, which is far from the probabilistic threshold of 95% or 98%. To reach the 95% or 98% probabilistic threshold for “adequate” reading for academic texts, 3500 to 8000 word families were recommended (Laufer, 2010; Hsu, 2011). This prompted the teachers, students and syllabus designers to think what vocabulary items should be learned next. Nation (2001& 2003) suggests that learners who have learned the high-frequency words and are in pursuit of academic study should quickly familiarize themselves with general academic vocabulary, such as the words on Coxhead’s (2000) Academic Word List (AWL) rather than the next 1,000 word families on the frequency list. The reason is that the academic words from AWL provide about 8.5% of text coverage yet the next 1,000 words on the frequency list often just provide about 4.3% of text coverage of the same corpus (Coxhead, 1998). Academic Word List (AWL) is also reckoned by Decarrico (2001) as target words to learn for students preparing for university studies. Learners on EAP track were suggested to learn a further one thousand high-frequency words beyond the 2000 base, plus the learning strategies to deal with low-frequency words. The further 1,000 word families were given priority. 21.

(33) to academic vocabulary. Thornbury (2002) also recommended students preparing for academic study to work on specialized academic word lists, such as the AWL. Academic words, also known as ‘sub-technical vocabulary’ (Cowan, 1974; Yang, 1986; Anderson, 1980), ‘semi-technical vocabulary’ (Farrell,1990) and ‘academic vocabulary’(Martin,1976; Coxhead,2000), refer to words such as accumulate, achieve, analysis and proportion, which are common in a wide range of academic texts but less frequent in general texts (Nation, 2001). Several attempts were made to investigate the vocabulary needed for academic studies in the 70s and four word lists were created for academic study from these researches (Champion & Elly, 1974; Ghadessy, 1979; Lynn, 1973; Praninskas, 1972). Considerable overlaps were found among the four lists by Nation & Xue (1984) and the four lists were combined into one list, the University Word List (UWL). UWL consists of 836 word families and provides 8.5% coverage of academic texts. The University Word List has been replaced by Coxhead’s (2000) the Academic Word List (AWL), which contains 570 word families. The academic words on AWL cover about 10% of the 3,500,000-token Academic Corpus of 414 academic texts across 28 subject areas of four major faculty sections: Art, Science, Commerce, and Law. The selection criteria were: range, frequency, and uniformity of frequency. In terms of “range,” word families have to occur across all four faculty sections and more than half of the 28 subject areas to be selected. This selection principle ensures the word families on AWL to be useful to students of all disciplines. As for the selection principle of “frequency,” word families have to occur over 100 times in the 3,500,000-token corpus to be included. This selection principle ensures that learners meet the word families a reasonable number of times when reading academic texts. The principle of “uniformity of frequency” rules that word families have to occur at least 10 times in each of the four faculty sections. This again ensures the usefulness of the AWL for learners studying various 22.

(34) disciplines. In addition, the word families that match the above-mentioned selection criteria yet appear on the General Service List were excluded to ensure the word families selected are of academic nature. On the basis of frequency of occurrence, the 570-word-family AWL has been divided into 10 sublists with each sublist containing 60 word families except for Sublist 10, which has only 30 word families. The word families on Sublist 1 occur more frequently than the ones on the subsequent sublists. Sublist 2 has the next highest frequent words. The academic words from the 60 word families on Sublist 1 account for about one third of the total coverage (3.6% text coverage) of that of the AWL list provides (10% text coverage) while the academic words from Sublist 2 provide only half of the coverage of Sublist 1(1.8% text coverage). The word families in the first three sublists occur with relatively high frequency (of 6.6% text coverage) and have been suggested to have the highest value for learning (Coxhead, 2000). Academic words are important learning goals for L2 learners in preparation for university study as these words were found to account for a substantial part of academic texts. The academic words from the AWL provide about 10% of the text coverage in the academic corpus of 3,500,000 running words (Coxhead, 2000). Several other researches have also reported on the text coverage of the academic words from AWL in a variety of disciplines. Cobb and Horst (2002) found the AWL provided text coverage of 11.6% in a self-compiled corpus of academic texts across several disciplines (e.g. linguistics, history, zoology, etc.). Text coverage of 10.07% offered by AWL was reported in the discipline of medicine (Chen & Ge, 2007). In the field of finance, Qian & Li (2010) demonstrated AWL text coverage of 10.46%. Vongpumivitch, et al. (2009) discovered 11.17% of text coverage of AWL in the Applied Linguistics discipline. These findings of the AWL text coverage from various disciplines are consistent with what Coxhead (2000) have reported and proved the 23.

(35) importance of studying the academic vocabulary compiled in the AWL for academic study. This study will examine the word selection in the senior high school English textbooks with the Academic Word List for its significant role in preparing students for further studies and focus on the examination of academic words from Sublist 1 and the first three sublists for the high text coverage they offer. Vocabulary in Textbooks The role of vocabulary in language textbooks received attention early in the 1930s when scholars like Faucette, Palmer, West and Thorndike (1936) worked on the principles for vocabulary selection for learning a foreign language. Despite the dominance of syntactic and phonological knowledge presented in the textbook in the 1960s and 70s, vocabulary has regained more researchers’ attention since the 1980s (Zimmerman, 1997). With the positive evidence found in support of explicit vocabulary instruction along with reading in ESL context (Paribakht & Wesche, 1997; Zimmerman, 1994) and support for explicit vocabulary instruction on high-frequency words for L2 learners (Beck, McKeown, & Omanson, 1987; Coady, 1997; Nation, 2001), textbooks writers place more emphasis on vocabulary or incorporate relevant research findings into the presentation of the vocabulary component of the learning texts. For example, the recently published language textbook series, Q: Skills for Success (Bixby, et al., 2011) published by Oxford University Press, incorporates words from Academic Word List, practices of collocation, and strategies for learning vocabulary. Based on findings from researches and teaching, there are concrete principles and evaluation criteria of vocabulary arrangement in textbooks for teachers and textbook writers to determine whether the vocabulary arrangement could facilitate the optimum vocabulary learning for the learners.. 24.

(36) Suggested Number of New Words As the issues of vocabulary size goal for L2 learners, which words to teach or learn first and the importance of explicit vocabulary instruction on high-frequency words for L2 learners have been discussed, this then would bring out the question of how many new words should be introduced or taught per class period or over the duration of a course. Gairns & Redman (1986) suggest that the optimum load for teachers to introduce new words to students in a 60-minute class period averages 8 to 12 productive items. The reasonable amount of new words introduced would vary depending on the students’ proficiency level and needs. Elementary students at beginner level could have fewer items while senior high school students at more advanced level could have a higher number of new words introduced. It is hoped that the lower level students would develop productive vocabulary knowledge of 1,000 items over 125 hours of study, which might help students acquire or learn the high-frequency words at a reasonable amount of time. However, Gairns & Redman (1986) also mentioned that the suggested number of new words cannot be equated to the learners’ successful acquisition of L2 vocabulary. Several other factors, such as learners’ motivation, aptitude, learning environment, learnability of the word, L1 interference, L2 exposure, would also influence learners’ vocabulary acquisition. Milton & Meara (1995) found the normal pace of classroom acquisition for L2 learners averages around 550 words per year. It seems reasonable that teachers introduce more new words than what the learners actually acquire at the end as attrition could happen. Schmitt (2000) also pointed out that introducing about 10 new words in a one-hour class period would be reasonable load for L2 students. Nation and Stuart (2011) proposed that L2 learners should at least try to match the native speaker rate of learning vocabulary, which was estimated to be around 1,000 words of receptive knowledge a year. For L2 learners studying in 40-week school year, 25 25.