An Empirical Study Of The Effects Of Different Output Tasks On Productive Vocabulary Acquisition

In most models of L2 vocabulary development, it is assumed that the act of learning a word usually progresses from receptive to productive knowledge. Many experimental studies found that L2 learners'productive vocabulary knowledge tends to lag far behind their receptive knowledge. Acquiring productive vocabulary knowledge is more complex than acquiring receptive vocabulary knowledge. Jullian uses lexical acquisition plateau to illustrate the phenomenon that L2 learners'productive vocabulary ability stops at a certain stage and can hardly progress any more. How to enhance learners'productive vocabulary acquisition becomes one of core issues in EFL teaching and learning. The present study was stimulated by EFL learners'inadequacy in productive word knowledge.Since the postulation of the comprehensible output hypothesis (COH) (Swain, 1985, 1995), many research studies have examined whether output could promote L2 lexical acquisition. The results of these studies indicated that oral output tasks or written output tasks could improve L2 vocabulary acquisition. However, few studies have ever examined whether oral output and written output would affect L2 productive vocabulary acquisition differently. The present study was designed to investigate the effects of different output task in improving productive vocabulary acquisition.In the field of language learning, writing has been advocated to be a more powerful tool of language learning than speaking. Writing is a more complex and demanding cognitive ability than speaking, so it requires more mental effort on the part of the learners than speaking does, and, thus written outputs are expected to produce more effective lexical learning effects than oral outputs, the learners performing the written task can acquire more vocabulary than those performing the oral task. Similarly, composition-written and text reconstruction are assumed to have different effects on the vocabulary acquisition. The writers within composition-written output are expected to be more motivated and hence should be more actively involved in the output activity than the participants in the text reconstruction tasks, since they are predisposed to think more about the how to use the words to organize the ideas, engage in more cognitive word processing, therefore, the writers within composition-written output are predicted to gain more word learning.Based on the above analysis, the present study aimed to explore how three different task types would affect L2 productive vocabulary differently. The output tasks in the present study are: a text reconstruction orally task, a text reconstruction task, and a composition task. The text reconstruction orally task group was asked to produce an oral reconstruction using the target words. The text reconstruction task group was required to reconstruct the content of the passage with the target words. The composition task was asked to write compositions with the target words.The present experiment was to answer the following research questions: (1) Do output tasks lead to L2 productive vocabulary acquisition? (2) Do written output task and oral output task lead to different levels of L2 productive vocabulary acquisition? (3) Do Composition task and text reconstruction task lead to different levels of L2 productive vocabulary acquisition?Altogether 57 first-year EFL students from Shandong University of Traditional Chinese Medicine participated in the study. They were randomly divided into three groups for three different output tasks.The whole experiment consisted of 4 phases: one pilot study, one pretest, the treatment and one posttest:20 first-year students and 20 second-year students, who would not be involved in the treatment, participated in the pilot study to choose the target words. The participants took a pretest to test whether they were on the equivalent levels of vocabulary knowledge before the experiment The three experimental groups were taught by the same teacher. And they were required to perform three different output tasks. One week later the participants took productive vocabulary posttest after task treatment. After the experiment, the data collected through the vocabulary posttest were analyzed by SPSS.Posttest results revealed the following research findings: (1) The three output tasks had helped participants to acquire target words and use them in production.(2) The results did not indicate any statistically significant differences between written output group and oral output group on the vocabulary acquisition. (3) The results revealed there was statistically significant difference between text reconstruction group and composition group. The former was more effective on productive acquisition than the latter.The results of the present study supported the previous research that output will lead to L2 productive vocabulary acquisition. The present study showed insignificantly different lexical acquisition of oral output and written output and significantly different lexical learning of reconstruction and composition. The findings were discussed with reference to task requirements and distribution of learners'attentional resources.The pedagogical implications of the findings and the suggestions for further research are discussed.