Introduction

As we all know, during the whole process of foreign language learning, vocabulary learning plays an extremely significant role. It is one of the essential components of a language is the unity of meaning and structure in the language system. One of the main difficulties for those EFL learners who want to achieve effective communication is the amount of words they need to acquire. Vocabulary size directly influences L2 learners mastery and application of the four basic English skillslistening, speaking, reading and writing. So far much research has done on incidental L2 vocabulary acquisition in the field of reading(Gai, 2003; Huang, 2004; Hulstijin Laufer, 2001). But little has been done on the effect of task type on EFL learners single word acquisition. This study is aimed to apply the involvement load hypothesis to investigate the two typesmultiple choice and cloze affect EFL learners incidental single word acquisition in listening.

Pedagogically, vocabulary is the base of any language, which is used to make up large structures like sentences, paragraphs and even whole passages. The acquisition and retention of single words have become one of the critical issues in second language learning and teaching. Because L2 vocabulary is critical important to L2 learners and teachers, facilitating learning and teaching L2 vocabulary requires studies concerning how various factors affect L2 vocabulary acquisition.

Theoretically, incidental vocabulary acquisition has become one of the focuses in the study of second language vocabulary acquisition. Those research achievements made by researchers from China and overseas not only improved public awareness towards the effectiveness of incidental vocabulary acquisition, but also broadened the thought of second language vocabulary teaching. Many researchers are interested in incidental L2 vocabulary acquisition through reading, and their studies are based on the involvement load hypothesis (Hulstjin Laufer,2001; Wu, 2010; Huang, 2004), and also the input frequency hypothesis (Brown, Waring, Donkaewbua, 2008; Vidal, 2003, 2011) and input-output hypothesis (Lei, 2011; Wang, Yao, Xu,2012). However, rare research was explored on whether the involvement load hypothesis, the input-output hypothesis and input frequency hypothesis can explain the incidental L2vocabulary acquisition through listening.

This research aims to see how the involvement load hypothesis contribute to incidental L2 vocabulary acquisition through listening. Hoping the findings of the research are valuable to EFL learners and teachers in the aspect of vocabulary learning and teaching by offering them some useful suggestions.

Literature review

Usually, second language vocabulary acquisition includes acquiring intentionally and incidentally by whether learners focus their attention on the word or not. The concept of incidental vocabulary acquisition was defined by Nagy, Herman and Anderson in 1985 on the basis of a study on childrens native language acquisition. It means that students attention is not on remembering new words but they remember them unconsciously when they are doing other tasks, like reading and communication (Schmidt 1994:165-210). According to Nagy et al. (1985), a big number of first language vocabulary knowledge children acquired is neither by consulting dictionary, nor from the formal classroom instruction, but gains in their daily life, such as communicating with others, reading stories, listening to radios and watching TV series and so on. Brown et al. (1999) pointed out that the term of incidental vocabulary acquisition can also be applied in second language acquisition. Wesche and Paribakht (1999) indicated that incidental vocabulary acquisition happens when learners focus on the meaning of the text they read, and not when pay attention to unknown words.

Hulstjin and Laufer (2001) thought the incidental acquisition as by-product of reading and listening activities not merely focus on vocabulary learning. As relative to incidental vocabulary acquisition, Hulstjin and Laufer (2001) stated that intentional vocabulary acquisition as the move aimed at purposely memorizing lexical information and making that information be accessible to read. Hulstjin and Laufer (2001) argued old in advance that in experiments investigating incidental vocabulary learning, learners are typically required to perform a task involving the processing of some information without being told in advance that they will be tested afterwards on their recall of that information. In contrast, participants in an intentional learning situation are told in advance that their recall will be tested afterwards (p.10).

Whether participants attention is on vocabulary or not (Wesche Parbakht, 1999), and whether the participants are told of the upcoming vocabulary test before learning(Eysenck, 1982) differ incidental second language vocabulary acquisition from intentional second language vocabulary acquisition on the basis of the experiment many researchers conducted.

In conclusion, when learners are busy with some other activities (reading, listening, writing and speaking), and there is no intention to learn new word but acquired new words incidentally-- this is how incidental L2 vocabulary acquisition takes place.

With regard to incidental vocabulary learning, (Laufer, B., J.H. Hulstijn, 2001) tentatively proposed the notion of the Involvement Load Hypothesis. This hypothesis has been developed based on the depth of processing model, which was first proposed by (Craik, F.I.M., R.S. Lockhart,1972). They recommended that retention in the long-term memory depends on how deeply information is processed during learning. Involvement is perceived as a motivational- cognitive construct, and retention of unfamiliar words is claimed to be conditional upon the amount of involvement while processing these words. (Laufer, B., J.H. Hulstijn, 2001) propose that the construct of involvement is composed of three components: need, search, and evaluation.

Need, as the motivational, non-cognitive dimension of involvement, is concerned with a drive to accomplish the task requirements, imposed either internally or externally, which is also used to distinguish between moderate and strong need. According to (Laufer, B., J.H. Hulstijn, 2001), need can occur in two degrees of prominences: moderate and strong. Need is hypothesized to be moderate when it is imposed by an external agent, for example, when the teacher asks students to use a word in a sentence. Need is strong when it is intrinsically motivated and self-imposed by the learners, for instance, when learners decide to look up a word in a dictionary while writing a composition.

Search is the attempt to find the meaning of an unfamiliar L2 word by consulting dictionaries, or the attempt to find the L2 word from expressing a concept by asking a language teacher, for example, trying to find the L1 translation of an L2 unknown word by looking it up in a dictionary. Although need has two degrees of prominence, i.e., either moderate or strong, there are two degrees of prominence for search. It is either present with index 1 or absent with index 0. When the meaning of an unknown word is given, that is, the attempt of search is not required, search id absent.

Evaluation entails a comparison of a given word with other words, a specific meaning of a word with its other meanings, or combining the word with other words in order to assess whether a word does or does not fit its context. Evaluation comprises of two potential degrees of cognitive processing: moderate and strong. Evaluation is moderate when learners must recognize differences between words provided in a given context (e. g. deciding which meaning of the target word best fits the context in which it is encountered) and strong when the task requires making decisions about new words and combining them with known words in original contexts (e. g. sentence and composition writing).

According to Hulstijn and Laufer (2001), when testing the effect of task-induced involvement on incidental L2 vocabulary acquisition, the task with higher involvement load contribute better vocabulary acquisition than the task that induce lower involvement load. Furthermore, tasks inducing the same amount of involvement load result in the same vocabulary acquisition. As they claimed, retention of unknown words was determined by the degree of involvement while processing words.

Research methodologyThis study will investigate how different listening tasks affect EFL learners vocabulary acquisition. To be specific, it will address the following two questions:1.Is the gap-filling task significantly different from the multiple-choice task in contributing to EFL learners receptive vocabulary knowledge of the target words?2.Is the gap-filling task significantly different from the multiple-choice task in contributing to EFL learners productive vocabulary knowledge of the target words?The two parts followed respectively show how the listening materials were chosen and how the tasks were defined.Passage. The listening materials should be chosen by two significant criteria. One of them is that the difficulty of the text should be appropriate for participants in the present study. The other one is that the topic is expected to be unfamiliar but attractive to participants, because interesting subjects would attract participants to focus on the listening material, meanwhile the familiar topic contributes to text comprehension and incidental vocabulary acquisition.Thinking of the language proficiency of the participants, three listening passages in this study were adapted from CET-6 model listening tests. These three passages were recorded in standard English with American accents. Moreover, the quality of the recording was quite clear without background noise. The length of these passages was approximately equal (2 minutes): the first one includes 276 words, and the second and the third one includes 246 and 218 words. Whats more, two professional English teachers predicted that , in the three passages, the percentages of possible unknown words were 2.8%, 3.8% and3.6%, which indicated that the difficulty levels of these passages were appropriate for these participants.Task. Two different tasks were developed on the basis of the listening materials. The first task involved multiple-choice provided three choices with the target word in. the second task involved gap-filling exercise and the target words were used to fill in the blanks.1)Group 1 (N =25): Listening comprehension twice plus three choices. Participants in group 1 were asked to listen to three passages twice and answer ten multiple-choice questions for each passage. 2)Group 2 (N =25): Listening comprehension twice gap-filling. Participants in group 2 were asked to listen to the same passage twice but instead of ten multiple-choice question, they should fill in ten blanks in each passage after listening.The experiment was administered to 50 sophomores of English learners, coming from two intact classes in Nanjing Tech University.Two months after sitting for CET-6 in April, 2013, the listening-related tasks and L2 incidental vocabulary acquisition test were administered in those students. All the participants were assigned into two groups at random and completed the tests in the two different classrooms for the different listening comprehension tasks. The only instructor in each classroom need to take charge of handing out and handing in the paper. All participants were demanded to listen to the same passages to get a general idea of them. And they were asked to perform different tasks when listening. Since the time on task is considered an inherent property of a task (Hulstijn Laufer, 2001), to decrease the interference of time, participants at the same level of input frequency were asked to finish the different listening tasks in the same time. A sheet of multiple-choice and the other of gap-filling were given to different groups. In this study, all the participants didnt know there would be a vocabulary for them later. After all data were collected, the participants could have a 10-minutes break.After that, all the participants were given an immediate L2 incidental vocabulary acquisition test. Then, all the test papers were collected to make a subsequent analysis.Every participants acquisition of receptive and productive knowledge of each target word was measured on Mins (2008) modified 4-item VKS in which each item was awarded zero point or one point. Because this research was aimed at studying the respective and productive word knowledge, thus only the last two items were scored.The aim of the third item was to test the participants L2 receptive vocabulary knowledge, and its scoring method was demonstrated as follows:0 point: the idea of the synonym or translation of the target word was not given correctly.1 point: the understanding of the meaning of the target word was given fully. It doesnt matter if there were wrong Chinese characters or Chinese phonetic symbols were used to replace right Chinese characters in the translation.The aim of the forth item was to test the participants L2 productive vocabulary knowledge, and its scoring method was similar to that of the third item.0 point: if the meaning of the target word was wrong, or the understanding of the meaning was correct but used incorrectly in the aspect of grammar, no point would be given. The grammatical misuses of the target word includes, the wrong tense or inflection of a verb, incorrect use of the active or passive voice of a verb, the incorrect use of the countable or uncountable nouns, misuse of the part of speech of the target word or put the original form of a verb immediately after a preposition, and so on.1 point: when the meaning and grammatical usage of the target word were right in the sentence, one point would still be given even if other parts of the sentence contained errors.Both the receptive and productive knowledge of each target word in the immediate test were scored by the researcher of this study and an independent rater according to the previous criteria. And both the receptive and productive vocabulary knowledge of each target word was discussed by two independent raters if any disagreement happened was 100%. Thus the inter rater agreement was 100%.On the basis of the research questions at the beginning of this chapter, the two task typemultiple-choice and gap-filling are the independent variables of the study. The dependent variable of the study is participants incidental vocabulary acquisition. In order to answer the research questions, the scores of the participants vocabulary acquisition were submitted to SPSS 17.0 for statistical analysis. Then independent samples t-test was conducted to find the main and interaction effects of each independent variable on participants incidental vocabulary acquisition.Conclusion:By using independent samples t-test to analyze the collected data, the present study has investigated how different listening tasks affect EFL learners vocabulary acquisition. It is predicted that there is significant difference between gap-filling and multiple-choice task in contributing to EFL learners receptive and productive vocabulary knowledge of the target words; furthermore, gap-filling task performs better than multiple-choice task in contributing to both receptive and productive vocabulary acquisition of EFL learners.

ReferencesBrown, C., Sager, S.L., LaPorte, C.(1999). Incidental vocabulary acquisition from oral and written dialogue journals. Studies in Second Language Acquisition, 21(2), 259-283Brown, R., Waring, R., Donkaewbua, S. (2008). Incidental vocabulary acquisition from reading, reading-while-lisening, and listening to stories. Reading in A Foreign Language, 20, 136-163.Craik, F. I. M., Lockhart, R. S.(1972). Levels of processing: A framework for memory research. Journal of Verbal Learning and Vernal Behavior, 11, 671-684.Eysenck, M. W.(1982). Incidental learning and orienting task. In C. R. Puff (Eds.). Handbook of research methods in human memory and cognition (pp.197-228). New York: Academic Press.Hulstijn, J. H., Laufer, B. (2001). Some empirical evidence for involvement load hypothesis in vocabulary acquisition. Language Learning, 51, 539-558.Nagy, W. F., Herman, P. A., Anderson, R. C. (1985). Learning words from context. Reading Research Quarterly, 20, 233-253.Schmidt, R. (1995). Consciousness and foreign language learning: A tutorial on the role of attention and awareness in learning. In R. Schmidt (Ed.). Attention and Awareness in Foreign Language Learning (pp. 1-63). Honolulu: University of Hawaii Press.Vidal, K. (2003). Academic listening: A source of vocabulary acquisition. Applied Linguistics, 24 (1), 56-86Vidal, K. (2011). A comparison of the effects of reading and listening on incidental vocabulary acquisition. Language Learning, 61(1), 219-258Wesche, M., Paribakht, T. S. (). Reading and incidental L2 vocabulary acquisition: An introspective study of lexical inferencing. Studies in Second Language Acquisition, 21, 195-224.Bao Gui.[鲍贵] Wang Juanjuan. [王娟娟]，(2013), 前词汇量和时间对任务作用于二语词汇附带习得的制约性[J]. 现代汉语, 2013 (4): 395-402.Gai Shuhua.[盖淑华], (2003). 词汇附带习得研究概述. 解放军外国语学院学报(2):73-76.Huang Yan.[黄燕], (2004). 检验投入量假设的实证研究阅读任务对中国学生词汇记忆的影响。 现代汉语(4): 386-394.Lei Lei. [雷蕾]，(2011). 词汇强化条件和语言水平对词汇附带习得的影响研究. 外语研究(1): 75-79.Lu Jing.[卢静], (2008). An Emirical Study of the Involvement Load Hypothesis in Incidental Vocabulary Acquisition in EFL Listening (Masters thesis). 浙江大学。Wang Tongshun, Yao Yu., Xu Yingying. [王同顺、姚禹、许莹莹]，(2012). 听读输入模式下二语词汇附带习得的对比研究. 外语与外语教学(6): 1-5.Wu Xudong. [吴旭东], (2010). 学习任务能影响词汇附带习得吗？投入量假设再探. 外语教学研究(2): 109-116.

Outline

1. Introduction 1.1 Need for the study 1.2 Research purpose2. Literature review 2.1 Incidental L2 vocabulary acquisition 2.2 The involvement load hypothesis and incidental L2 vocabulary acquisition 2.3 Related empirical studies 2.4 Limitations in the previous studies3. Methodology 3.1 Research questions 3.2 Variables and operational definitions 3.3 Data collection 3.4 Data analysis 4. Results and discussion4.1 Results4.2 Discussion5. Conclusion5.1 Major findings of the study5.2 Implications 5.2.1 Theoretical implications 5.2 2 Pedagogical implications5.3 Limitations and suggestions for future research