1. 研究目的与意义（文献综述包含参考文献）

introduction1.1 research backgroundvocabulary plays an important role in english learning and teaching. without grammar, only a little can be expressed; without words, nothing can be expressed. a british psycholinguist (meara, 1980), published the article "vocabulary acquisition is a neglected aspect of language learning" in the journal language teaching and linguistics. since then, topics about vocabulary in various aspects have been brought into a heated debate. numerous studies of different kinds have been carried out gradually. the emphasis of the study is mainly on the breadth (generally refers to the vocabulary size) and the depth (the proficiency in using various aspects of vocabulary). 1.2definitions1.2.1 vocabulary abilityvocabulary level is the core of language proficiency. the size of vocabulary and vocabulary breadth are the important barometers of english learners' language level. for l2 learners, mastering language-wise, understanding and using words properly can be a great difficulty, considering how basic and indispensable vocabulary is in linguistics.while with the gradual deepening and broadening of learners' mastery of foreign languages, grammatical problems tend to be less and less. more likely, choke points come from the concept and connotation of vocabulary knowledge. second language or foreign language researchers have put forward different but complementary theoretical frameworks. most people agree that vocabulary knowledge is not single or independent, it should at least include quality and quantity aspects, referring to the breadth knowledge of vocabulary or the depth knowledge of vocabulary. what is known is not only new vocabulary learning, but also new vocabulary development. therefore, vocabulary competence includes two dimensions: breadth and depth of learners' vocabulary learning, and the two should be compared. the former refers to the total amount of vocabulary learners learn --- vocabulary size, which only reflects the learners' passive vocabulary knowledge, or the ability to understand the most commonly used meaning of a word; the latter refers to the quality of vocabulary learning, that is, the ability to accurately and appropriately use words.the breadth and depth of vocabulary are closely related to and independent of vocabulary competence. therefore, vocabulary competence includes the ability to understand the common meanings of words and the ability to use or produce. the improvement of vocabulary competence is a dynamic and continuous process, which runs through the whole process of language learning and directly reflects the learners' language ability.1.2.2 comprehensive language competencelinguists and applied linguists have studied and discussed the concept and connotation of language competence in the past few decades, and their understanding of it has been developing and deepening gradually. based on this, american applied linguists put forward a more comprehensive model of language competence, which considers that language competence consists of language organization ability and language using ability. the former refers to the ability to organize language structure when generating or identifying grammatically correct sentences, understanding their subject content and arranging them into texts. the latter refers to the ability to determine how utterance, intention and language using environment relate to each other and form meanings, including elements that enable us to associate words and utterances with their meanings, with the intentions of language users, and with the relevant features of language using. language using ability consists of functional competence and sociolinguistic competence. according to the above theoretical model of language competence, language competence can be summarized as phonetic, grammatical and lexical knowledge and the ability to understand and produce correct sentences or utterances by using these knowledge. however, in practice, this concept is embodied in the application of multiple skills. therefore, in the context of teaching, this kind of language ability is called comprehensive language using ability.the ministry of education of the people's republic of china issued the english curriculum standard for full-time compulsory education in general senior middle schools. the overall goal of english curriculum in basic education stage is to cultivate students' comprehensive language ability. the formation of language comprehensive ability is based on the overall development of students' language skills, language knowledge, emotional attitude, learning strategies and cultural awareness. language knowledge and skills are the basis of comprehensive language using ability; cultural awareness is the guarantee of proper use of language; emotional attitude is an important factor affecting students' learning and development; and learning strategies are the guarantee to improve learning efficiency and develop autonomous learning ability. based on the existing theories of language competence, this definition covers the main contents of the framework of language competence and transforms it into an operational level of competence cultivation in language teaching, thus clarifying the specific training objectives of language teaching.1.2.3vocabulary breadth and language comprehensive abilityas for the influence of vocabulary ability on learners' comprehensive language ability, the academic research focuses more on the correlation between vocabulary size and language comprehensive ability. foreign studies have found that there is a significant positive correlation between vocabulary size and language proficiency. for example, seyyed m. a. and ishaaq a. find that performance in three of the toefl test items (guessing vocabulary, stated detail, and main idea) correlate to the overall performance in vocabulary levels test. while some results of similar studies are different. therefore, the correlation between vocabulary size and language comprehensive ability needs to be further verified. in any case, vocabulary size can predict the change of language ability to a certain extent. research shows that improving learners' comprehensive language ability by increasing their vocabulary is still an effective way. for instance, thamer a.(2019) provides suggestions for future studies on vocabulary and speaking link by finding out the facts that on some specific word levels, vocabulary knowledge will make a contribution to predicting speaking performance. some studies have shown that the influence of vocabulary size on language is different among learners at different levels. although vocabulary size has an impact on language comprehensive ability, it is different for students with different language proficiency. according to the study of mostafa j. e. and seyed m. r. a.(2020), the results show that vocabulary size and depth had a significant correlation for the lower-intermediate students; size and depth dimensions had a moderate association for the upper-intermediate participants; vocabulary size and depth were not significantly correlated for the advanced efl learners. this shows that there are many factors that affect language comprehensive ability, and vocabulary size is only one of them. the advantages of middle language level learners in language comprehensive ability mainly come from factors other than vocabulary size.1.3 literature reviewthis chapter provides a general view of effects of vocabulary on english proficiency in previous studies both home and abroad.1.3.1 foreign studies of the effects of vocabulary on english proficiencyabout three decades ago, some foreign researchers, goulden, nation and read(1990), make an investigation on the vocabulary of native language learners, which shows that their vocabulary is about 17000 words, and the number of vocabulary acquired every day is 2-3. nation(1993) provides the steps of how to select words from dictionaries to design a more accurate and scientific vocabulary questionnaire. in terms of the effects of vocabulary on listening, joshua m.(2018)s research shows that knowledge of words in the aural form from high to mid-frequency, and beyond, will provide learners with an important foundation of linguistic knowledge supportive of l2 listening capabilities.lars stenius sthr(2009) also makes an investigation on 115 advanced danish learners of efl and finds that the dimensions of depth and breadth of vocabulary knowledge are found to be significantly correlated with listening comprehension and can predict half of the variance in the listening scores. reading performance-wise, david d. qian(2002) finds that the dimension of vocabulary depth is as important as that of vocabulary size in predicting performance on academic reading and that scores on the three vocabulary measures tested are similarly useful in predicting performance on the reading comprehension measure used as the criterion. dongbo zhang(2012) also finds that vocabulary knowledge relates significantly to reading comprehension and grammatical knowledge shows a weak contribution to reading comprehension after controlling for the effect of vocabulary knowledge. furthermore, lars stenius sthr(2008) finds that learners receptive vocabulary size is found to be strongly associated with their reading and writing abilities and moderately associated with their listening ability. however, vocabulary size can still explain a significant and substantial portion of the variance in the listening scores.1.3.2 domestic studies of the effects of vocabulary on english proficiencydomestic researchers also make their efforts in verifying previous results and finding new relations on this subject. lu changzi(2004) investigates the relationship between the breadth and depth of vocabulary and the comprehensive language ability. the study shows that vocabulary size can only predict 34.7% of language comprehensive ability. for learners of different language levels, the predictive power and influence mode of vocabulary size on language comprehensive ability are different. in the aspect of reading, zhang xuebin and qiu tianhe(2006) carry out an empirical study on the relationship between the breadth and depth of vocabulary knowledge and reading in efl environment. it shows that there is a high positive correlation between vocabulary size, vocabulary depth and reading performance and the correlation between vocabulary depth and reading performance is more obvious. li xiao(2007) has the similar results in the study on the relationship between vocabulary size, vocabulary depth knowledge and comprehensive language ability. in addition, li jie(2015) finds that vocabulary breadth not only has a significant effect on second language reading, but also moderates the effect of metacognitive knowledge on second language reading.in terms of listening, zhang xiaodong(2011) finds that vocabulary breadth knowledge can explain 27% and 24% of the differences in listening comprehension and dictation scores in the study of the relationship between vocabulary knowledge and listening comprehension in cet-4. writing-wise, bai lifang and dai chunyan(2013) explores the different effects of cognition, spelling and collocation knowledge on reading and writing at 2000, 4000 and 6000 vocabulary levels. the study shows that collocation 2000 is the most relevant and the only predictor of writing, which can explain 24.8% of the difference. the predictive power of vocabulary ability to reading is higher than that to writing. translation-wise, through the comparative analysis of voa special english news and standard english news, yang fan and chen dong(2019) find that 1500 words can realize the transmission of meaning and information. combined with the study of related theories, students can quickly improve their expression ability. 1.4 need of the studymost of the above-mentioned researchers use questionnaires or test performances to investigate the breadth or depth of vocabulary of different language learners, or study the relationship between the breadth and depth of english vocabulary and the abilities of listening, speaking, reading and writing. then the results are analyzed and summarized to draw a conclusion. as for the relationship between the breadth of english vocabulary and english listening, speaking, reading, writing and translation, some of the existing research shows that the breadth of english vocabulary has a high positive correlation with reading comprehension, listening and writing, and also has a certain relationship with comprehensive language ability.it is a fact that quantitative researches are affected by many indeterminacy factors, so the conclusions drawn by predecessors deserve to be proved or corrected by new data or research methods repeatedly. in terms of research objects, in recent years, most of the researches are focused on college students, while the research on senior high school students is less, while there is less research on the relationship between students' vocabulary breadth and english comprehensive ability under the high school teaching environment. 1.5 research purposesas shanghai boasts to play a leading role in english education in china, its english difficulty of college entrance examination often invite intense scrutiny. consequently, to have better performance in the exam, students should get an overall view of a more scientific way to improve english proficiency, and teachers should set up more efficient teaching methods. to achieve this, learning the correlations between vocabulary ability and comprehensive english competence is of top priority. thus, in this study, we investigate the relationship between english vocabulary breadth and their english comprehensive ability in four classes of grade two in shanghai east high school under the parallel teaching mode, and find the correlation between the two, providing some useful data reference for english learning and english teaching.referencesdavid, d.q.(2002). investigating the relationship between vocabulary knowledge and academic reading performance: an assessment perspective. language learning, 52(3), 513-536.dongbo, z.(2012). vocabulary and grammar knowledge in second language reading comprehension: a structural equation modeling study. the modern language journal, 96(4), 558-575.goulde, r., nation, p., read, j. (1990). how large can a receptive vocabulary be? applied linguistics, (4), 341-363.joshua, m. (2018). vocabulary for listening: emerging evidence for high and mid-frequency vocabulary knowledge. system,72, 23-36. lars, s. s.(2008). vocabulary size and the skills of listening, reading and writing. language learning journal, 36(2), 139-152.lars, s. s.(2009). vocabulary knowledge and advanced listening comprehension in english as a foreign language. studies in second language acquisition, 31, 577-607.meara, p. (1980). vocabulary acquisition: a neglected aspect of language learning. language teaching, 13, 221-246. mostafa, j. e. seyed, m. r. a. (2020). the relationship between vocabulary size and depth for iranian efl learners at different language proficiency levels. iranian journal of language teaching research, 8(2), 97-114.nation, i. s. p. (1993). using dictionaries to estimate vocabulary size: essential but rarely followed procedures. language testing, 10, 37-40.seyyed m. a. ishaaq a. (2012). the role of vocabulary size in predicting performance on toefl reading item types. system, 40, 376-385.thamer a. (2019). investigating the relationship between vocabulary knowledge and fl speaking performance. international journal of english linguistics, 10(1).白丽芳,戴春燕(2013),不同等级与层面的词汇知识对阅读和写作水平的影响,《外语教学理论与实践》，（2），72-78。

李洁(2015),元认知知识、词汇广度和二语阅读水平 关系研究,《中国外语》，（5），57-67。

李晓（2007），词汇量、词汇深度知识与语言综合能力关系研究，《外语教学与研究》，（5），352-400。

2. 研究的基本内容、问题解决措施及方案

Research content: The effects of vocabulary on various English performances (listening, grammar, reading, etc.), and the correlation between various English performances (listening, grammar, reading, etc.).Research methods: Apply statistical methods and software to perform statistical analysis on the surveyed data, which is divided into the following four stepsSampling survey. We conducted a survey on the vocabulary level of the students in the three classes of the second grade of the East Shanghai high School, Vocabulary testing is done on the website of http://testyourvocab.com. Computer-based exam results of English were obtained from the English teacher. Exploratory analysis.We perform preliminary processing of the data, detect outliers and eliminate them, and then examine the distribution and variability of the data. 3) Effect of vocabulary on English scoresUse relevant knowledge of statistics to study the effect of vocabulary on various English scores (listening, grammar, reading).4) Correlation analysisTo study the relevant characteristics of English scores (listening, grammar, reading).