任务教学对商务英语词汇的作用

ively master and apply target BE vocabulary in business environment.In this study，case-based teaching, one important teaching method which isbased on the carrier of cases was involved. One prominent characteristic of case-basedteaching method is showed by its reflection of essential communicative role of thelanguage. The teaching process needs a variety of materials which accord to practicalsituations. With the organization of teaching and learning activities, learners aresupposed to communicate and practice their linguistic knowledge in nearly truecontext. The case-based teaching is originated in tiie pedagogical practice in HarvardLaw School，with its development and evolution, this teaching method is generallyaccepted and applied in other fields and has achieved great effect. Generally,case-based teaching is defined as a type of teaching activity in which a specific realcase is explained and described. And the learners are guided to discuss and analyzethe issues in the case and are required to seek out solutions solving the problemsthrough the whole process. On completing' the tasks，learners develop theircross-cultural communicative ability in business cases. The present study examinedwhether this pragmatic teaching method enhance the incidental acquisition of BEvocabulary through the comparison with the traditional self-reading task.

Purpose of the Study

According to the researches and theories of incidental vocabulary acquisitionand case-based teaching, the lexical acquisition in the learning process of case-basedteaching is incidental. And this teaching method properly meets the needs ofdevelopment and mastery of Business English. The author of present study designedtwo different text-based tasks which involved two types of incidental vocabularyacquisition; case-based-teaching-involved task and self-reading task, investigatingwhether and how Business English vocabulary can be acquired incidentally throughcase-based-teaching-involved task.Research questions of the present study are listed as follows;(1) In the immediate test，which task shows more obvious enhancing effect onthe receptive acquisition of target BE words，the self-reading task or thecase-based-teaching-involved task?(2) In the immediate test, which task shows more obvious enhancing effect onthe productive acquisition of target BE words，the self-reading task or thecase-based-teaching-involved task?(3) In the delayed test，which task more obviously enhances the long-termreceptive acquisition of target BE words，the self-reading task or thecase-based-teaching-involved task?(4) In the delayed test，which task more obviously enhances the long-termproductive acquisition of target BE words，the self-reading task or thecase-based-teaching-involved task?

Chapter TwoTheoretical Foundation

In this chapter, the theoretical frameworks of present study are presented. Theauthor first tries to elaborate the theories of incidental vocabulary acquisition andimplicit learning, and then Depth of Processing Hypothesis and Involvement LoadHypothesis is introduced. Theories about English for Specific Purposes, especiallyabout Business English are also reviewed. At last, the case-based teaching waspresented as pedagogic theoretical basis of this study.Incidental Vocabulary Acquisition and Implicit LearningBackground and Terms of Incidental Vocabulary AcquisitionIn the process of learning and acquisition of a language，learners constantlyexperience two different types which are two distinctive terms in researches of secondlanguage learning: implicit learning and explicit learning. These two terms aregenerated from psychological studies and are in accordance with N. Ellis'sterminology;Implicit learning is acquisition of knowledge about the underlying structure ofa complex stimulus environment by a process which takes p