Proposal The Effects of Vocabulary and Grammatical Knowledge on the Inference of Word Meanings 1.Introduction The present study is aimed at exploring the effects of vocabulary knowledge and grammatical knowledge on EFL learners#8217; word inference. This chapter presents the concise background of the current study, aims of the study, and the organization of the study. 1.1 Background of the study Vocabulary plays an important part in L2 acquisition and is closely related to language understanding and reading performance. Vocabulary is taken as an essential part both in teaching and learning. Since 1970s, vocabulary acquisition has attracted many scholars#8217; attention. Numerous theoretical and empirical studies had been done to identify teaching methods of vocabulary acquisition. (Knight, 1994; Keating, 2008; Wu Xudong, 2010; Eckerth Tavakoli, 2012; Yue Yinglai, et al.; 2012).Researchers conducted extensive studies on the breadth and depth of vocabulary, vocabulary learning strategies, vocabulary acquisition process, vocabulary acquisition methods and vocabulary mental representation from different perspectives of psychology, semantics, pragmatics, corpus and cross culture. Large number of theoretical and empirical research work leaves us a clear cognition of the nature of vocabulary acquisition. What#8217;s more, most words in both first and second languages are probably learned incidentally through guessing the meanings of unknown words in extensive reading and listening process (Nagy, et al, 1985). Therefore, lexical inference is widely adopted by second language learners in dealing with new words (DE Bot. Etal., 1997). At the same time, the inference of word meanings is one of the most effective reading strategies (Oxford Crookall, 1989;Twaddell, 1973).Carnine et al. (1984) pointed out that using lexical inference instead of a dictionary can make reading process more smooth, not broken. A group of researchers both at home and abroad study the lexical inference from different perspectives, aimed at revealing the complex cognitive process of it, including ascertaining the source of knowledge and classified framework of inferencing strategies used in this process,(Carton, 1971; Haastrup,1987,1991; de Bot et al.,1997;Paribakht Wesche, 1999;Bengleil Paribakht,2004;Qian,2005;Nassaji,2003,2006;Wang Ying,2007;Hamada, 2009;Hu Nassaji, 2012),and studying the effects of EFL learners#8217;language proficiency ( Haastrup， 1991; Chern， 1993; Morrison，1996; Soria， 2001; Bengleil ＆ Paribakht，2004;Cai WeiWu Yian,2007; Shen，2009; Alavi ＆ Kaivanpanah，2009; Wang Ying，2011; Kaivanpanah ＆ Moghaddam，2012) 、vocabulary knowledge ( Nassaji， 2006; Qian， 2005; Xun YangSun Li， 2006;Wang GaiYan Wanglin， 2011) , grammatical knowledge ( Paribakht，2004; Alimorad et al.，2010) , cognitive style ( Alavi ＆Kaivanpanah， 2009; Shen， 2010; Wang Ying， 2013), topic familiarity and passage sight vocabulary ( Pulido， 2007), lexicalizing of mother tongue( Paribakht，2005;Wesche ＆ Paribakht，2009)on lexical inference. The process of the inference of word meanings is complicated and cognitive. Compared with the foreign, domestic existing studies mostly put forward various methods and techniques of guessing word meanings (Chen Xiaowei, 1995; Ma Wenying, 2003). The empirical research began to develop in the late 1990s.However,there is lack of research on the word inference and the research rarely studies on the effects of grammatical knowledge on the word inference and they mostly pay attention to the role of vocabulary knowledge in inferring word meanings instead of exploring their interactive effects on lexical inference. Given these limitations in the previous research, the present study is designed to make some contributions to the inference of word meanings from the perspectives of vocabulary and grammatical knowledge. Through the study, it attempts to help the EFL learners to improve the ability of lexical inference and reading ability, realizing the importance of learning vocabulary and grammatical knowledge, and contribute the methods of pedagogy and further study of influence of linguistic factors on the inference of word meanings. 1.2 Aims of the study Although a number of studies related to lexical inference have been conducted both at home and in the past(Oxford Crookall,1989;Twaddell,1973; Carnine,1984; Nation,2001; MondriaWitde Boer,1991; Nassaji,2006; Kondo-Brown,2006; ParibakhtWesche,1999; Fukkink,2002; 巧(Chen Xiaowei,1995; Ma Wenyin,2003; Liu Jinkai,1999; Wang Yin,2011; Meng Yue, 2004;), their focus was mainly based on the factors like vocabulary knowledge, topic familiarity and background knowledge and compared with the foreign, domestic existing studies mostly put forward various methods and techniques of word inference (Chen Xiaowei, 1995; Ma Wenying, 2003),lacking empirical studies. Moreover, a few domestic empirical studies focus on the effect of vocabulary knowledge on word inference, especially vocabulary depth. Therefore, there remains a need to examine more factors such as grammatical knowledge and conduct more research on lexical inference, aiming at understanding EFL learners#8217; lexical inference in the reading process. The current study is a continuation of previous research on lexical inference based on the input-output hypothesis and the involvement load hypothesis. Through the literature and limitations reported, this study summarizes linguistic factors affecting lexical inference, such as vocabulary breadth, vocabulary depth and grammatical knowledge and investigate the nature of the effect and interaction of the reader-based variables. The primary purpose of the study is to explore how the reader-based variables, i.e. vocabulary breadth, vocabulary depth and grammatical knowledge, and how large their respective explanatory power is. The study also aims to explore differences among these variables in contributing to L2lexical inference. 1.3 Organization of the study The thesis consists of five parts. Chapter One serves as the brief introduction to the research background, the importance of the research, the research purpose and the general layout. Chapter Two reviews research that motivates and generates the research questions addressed in the present study. It includes major theories about lexical inference and some major findings from the related empirical research both at home and abroad. Gaps in the previous research are subsequently recognized. Chapter Three presents the methodology of the study, consisting of the research design, subjects, instruments, selection of the target words, implementations of the experiment and the reliability of the tests. Chapter Four presents the results and discussions. It includes descriptive statistics, correlation matrix analysis and a multiple linear regression analysis in reference to each research question and in relation to previous relevant research findings. Chapter Five summarizes the major findings, discusses theoretical and pedagogical implications of the research, and indicates its limitations as well as suggestions for future research. Summary of the research This project examines the performance of subjects#8217; knowledge in vocabulary size test, word associate test, syntactic knowledge test, lexical inference in reading test. As is known to all, vocabulary knowledge is of great help to foreign language learning as well as grammatical knowledge. Besides, lexical inference is a useful strategy applied to English learning both in reading comprehension and listening. The literature suggests that vocabulary knowledge has a significant effect on the strategies of lexical inference. In particular, vocabulary depth has a stronger contribution to inferring word meanings than vocabulary breadth does. Comparatively, grammar knowledge#8217;s explanatory power is not as strong as vocabulary depth. Although, there are many studies abroad having been carried on to research on the influence of reader-based and non-reader- based elements on lexical inference, they rarely focus on the difference between vocabulary knowledge and grammatical knowledge affecting lexical inference. Most of them emphasize on the importance of vocabulary depth, context and topic familiarity, etc. Moreover, existing domestic research mainly concludes the techniques and methods of lexical inference, seldom conducting empirical studies. A few studies focus their attention on the functions of vocabulary knowledge. There exists a need for studying the effect of grammatical knowledge on lexical inference and its difference compared with vocabulary knowledge. This study attempts to investigate the influence of grammatical and vocabulary knowledge on word inferencing. Subject#8217;s knowledge of vocabulary and grammar will be tested first of all. Their respective functions to inferring words and the different explanatory power will be discussed in this study through their performance of lexical inference in the reading test. Purpose of the research The purpose of the study is to clarify the function of vocabulary and grammatical knowledge to lexical inference, instead of simply summarizing and describing the techniques of methods from these two aspects. Then the present study will discuss how different these elements contribute to lexical inference and explore pedagogical implications of the study. Relevant background literature Lexical inference has long been considered as a widely used way of dealing with new words (de Bot.etal.,1997), which is also thought to have something to do with incidental vocabulary acquisition. At the same time, the inference of word meanings is one of the most effective reading strategies (Oxford Crookall, 1989;Twaddell, 1973).Carnine et al. (1984) pointed out that using lexical inference instead of a dictionary can make reading process more smooth, not broken. Goodman, an American psychologist, said reading is a kind of psychological language guess game. Effective reading doesn#8217;t depend on accurate perception and recognition of all language elements, but depends on reader's reading skills. Lexical inference is a very important skill in reading. Using this skill can effectively accelerate the reading speed, improve reading ability, and enhance the reading interest. As a result, the study of lexical inference attracts people#8217;s attention and focus. In 1945 Seibert in Modern Language Journal published "A study on the practice of guessing word meanings from a context ", causing the attention from psychological circles and opening the prelude of research on word inferencing. After 1970, guessing word meaning gradually aroused the concern of the linguistic circles and people primarily research on factors affecting the guessing of word meanings and discuss the steps and methods of lexical inference. After 1990, lexical inference gradually became a hot issue in the field of research on the second language acquisition. A group of researchers both at home and abroad study the lexical inference from different perspectives, aimed at revealing the complex cognitive process of it, including ascertaining the source of knowledge and classified framework of inferencing strategies used in this process,(Carton, 1971; Haastrup,1987,1991; de Bot et al.,1997;Paribakht Wesche, 1999;Bengleil Paribakht,2004;Qian,2005;Nassaji,2003,2006;Wang Ying,2007;Hamada, 2009;Hu Nassaji, 2012),and studying the effects of EFL learners#8217;language proficiency ( Haastrup， 1991; Chern， 1993; Morrison，1996; Soria， 2001; Bengleil ＆ Paribakht，2004;Cai WeiWu Yian,2007; Shen，2009; Alavi ＆ Kaivanpanah，2009; Wang Ying，2011; Kaivanpanah ＆ Moghaddam，2012) 、vocabulary knowledge ( Nassaji， 2006; Qian， 2005; Xun YangSun Li， 2006;Wang GaiYan Wanglin， 2011) , grammatical knowledge ( Paribakht，2004; Alimorad et al.，2010) , cognitive style ( Alavi ＆Kaivanpanah， 2009; Shen， 2010; Wang Ying， 2013), topic familiarity and passage sight vocabulary ( Pulido， 2007), lexicalizing of mother tongue( Paribakht，2005;Wesche ＆ Paribakht，2009)on lexical inference. In terms of level of measuring lexical inference, different researchers have used different methods. Some researchers adopt multiple choices. More and more researchers, like foreign scholars Jenkins (1989), Nassaji (2003), and domestic scholars Xun Yang, Sun Li (2006), Wang Ping (2009) use short answer questions and three-level scoring methods to elevate students#8217; ability of lexical inference. Among those research based on the readers#8217;factors affecting the inference of word meanings, however, there is lack of research based on vocabulary knowledge and grammatical knowledge. Vocabulary for native or native language acquisition is vitally important. It is considered to be an essential building block o f language (Schmitt, Schmitt Clapham, 2001).In the study of second language acquisition, the study of vocabulary was not taken seriously until the 1980 s. A famous linguist Frank Smith has also pointed out that most of the readers#8217; vocabulary is from meaningful reading. New words are learned from context by using known knowledge. Nation and Coady (1988) think it is only when 95% of the words in the reading text are known that it is possible to construct enough contextual knowledge and successfully guess the meaning of new words. Laufer (2001) also pointed out that the 3000 word family can cover 90% - 95% vocabulary of plain text. Words are often divided into receptive and output vocabulary. In recent years, from the angle of quantity and quality of words that learners master, vocabulary knowledge is divided into the breadth and depth of vocabulary. Large enough vocabulary is the precondition of successful inferring word meanings. Marzban Hadipour#8217;s research shows that the ability of inference is highly related to the breadth and depth of vocabulary. The predictive power of vocabulary depth in contributing to inferencing is stronger than the breadth of vocabulary. Nassaji surveyed the relationship between the depth of vocabulary knowledge and lexical inference. The results showed that the rich vocabulary depth contributes obviously to the successful inference of word meanings. Wilkins said without grammar, many things are difficult to express. The importance of grammatical knowledge to reading comprehension is evident, because it is very key to the construction of discourse coherence (Giv 'on 1995).Also it integrates the words generating propositional meaning, finally constructing a model of text discourse and the basis of mental models (Perf ett I t 1995 Brit; Kintsch 1998; Fender 2001). Lack of necessary grammar knowledge can also affect the monitoring process of reading comprehension (Bowey 1986). In the research domain of second language, Alderson (2000) had explicitly pointed out that "certain grammatical structure kowledge, or the processing capacity of the structure is importance to second language reading, and that" the ability of decomposing a sentence into the correct grammar structure should be an important part of text comprehension (Berman). The process of the inference of word meanings is complicated and cognitive. Compared with the foreign, domestic existing studies mostly put forward various methods and techniques of guessing word meanings (Chen Xiaowei, 1995; Ma Wenying, 2003). The empirical research began to develop in the late 1990s.However, there is still research on the word inference and the research rarely studies on the effects of grammatical knowledge on the word inference and they mostly pay attention to the role of vocabulary knowledge in inferring word meanings, not to mention the question that which one of the two is a more important element in the inference of word meanings.