Effects Of Task-induced Involvement And Learner Proficiency On Junior High School Students’ English Incidental Vocabulary Acquisition:an Empirical Study

Vocabulary acquisition has been the key and difficult issue in Second Language Acquisition (SLA). Since learners can just learn limited words in class, much vocabulary will be acquired incidentally by reading. According to Involvement Load Hypothesis (ILH) put forward by Laufer and Hulstijn (2001), task-induced involvement is composed of three components:Need, Search and Evaluation, and its index is the sum of the above three components. So far as this hypothesis is concerned, the higher the amount of task-induced involvement is, the better the incidental vocabulary acquisition can be. Later, many researchers tried to verify ILH from different perspectives, and the results turned out to be inconsistent. Some studies (e.g. Ghprbani2012) confirmed ILH completely, while others (e.g. Zhou2009) did not fully support it.Based on Incidental Vocabulary Acquisition (IVA), ILH and so on, the present study tried to explore the effects of task-induced involvement and learner proficiency on Junior High School students’English incidental vocabulary acquisition, aiming to answer two research questions:1) When the learners are at the same proficiency level, what is the effect of the different levels of task-induced involvement on Junior High School students’English incidental vocabulary acquisition?2) When task-induced involvement loads are of the same level, what is the effect of the different levels of learner proficiency on Junior High School students’English incidental vocabulary acquisition?The main findings in the present study are:1) When the learners are at the same proficiency level, the task with higher level of task-induced involvement produced better English incidental vocabulary acquisition.2) When the task-induced involvement loads are of the same level, learners with higher proficiency level brought better English incidental vocabulary acquisition. These findings verified the positive effect of task-induced involvement on English incidental vocabulary acquisition.Consideration the limited vocabulary of research subjects, we only focused on some common parts of speech when choosing the target words. Besides, as the glossaries of the target words were provided, the effect of Search in the task-induced involvement was therefore neglected. Even so, the study still has some limitations.