The Effects Of Explicit/Implicit Instruction And Working Memory On Acquisition Of Explicit/Implicit Knowledge

Recently, with the different opinions on the role of attention in SLA, the effects of explicit/ implicit instruction on acquisition of second language knowledge have been extensively investigated. However, the current results are still in great dispute. On the one hand, the depth and width of these researches are limited and the empirical studies are not sufficient. On the other hand, when it comes to the individual difference factors, most of the studies only take learners‘ language proficiency into account, instead of the working memory. Thus it is essential that further investigations and experiments should be conducted with working memory to offer some advice for teachers and to accelerate the learning of English as a foreign language in China.By using the quantitative and qualitative researches methods, the present study aims to investigate the differential effects of explicit/implicit instruction and working memory on relative clause on the measures of explicit and implicit knowledge. The research questions are as follows:1) How will explicit/ implicit instruction affect the acquisition of explicit/ implicit knowledge? How is its delayed effect?2) How will learner‘s working memory capacity affect the acquisition of explicit/ implicit knowledge under explicit/ implicit instruction? How is its delayed effect?There are 90 sophomores from a vocational college are the subjects of this study. They are not English majors and from three paralleled chasses which are named explicit instruction(EI) group, implicit instruction(II) group and control instruction(CI) group respectively. The reading material is adapted from Izumi(2000) containing the target forms with a few changes on the difficult words to make the participants clear. There are three periods of the current study: pretest, immediate posttest and delayed posttest. The pretest contains the reading span test for measuring working memory capacity and explicit/ implicit knowledge pretest. In the immediate posttest, 45 mins of explicit instruction was delivered for the EI group, 45 mins of implicit instruction was carried out for the II group and CI group, the only difference for the CI group lies in the reading material, there is no text enhancement for the CI group. After instruction, untimed grammaticality judgment test(UGJT) and timed grammaticality judgment test(TGJT) were carried out to examine learners‘ explicit knowledge and implicit knowledge respectively. In the delayed posttest, similar UGJT and TGJT were used to test their delayed explicit and implicit knowledge. After the tests, 6 participants from each group with one high WMC and one low WMC were interviewed.As demonstrated in the results: 1) the EI group outperform the II group and CI group both on acquisition of explicit and implicit knowledge, especially for the explicit knowledge. While for the acquisition of implicit knowledge, explicit instruction shows a promising effect only drop soon in the delayed posttest. Besides, II group and CI group exhibit a climbing trend, explicit knowledge especially. The results support the positive role of attention in the acquisition of L2, indicate that explicit instruction is not only helpful for the acquisition of explicit knowledge but also for that of implicit knowledge. Implicit instruction is good at retaining knowledge while explicit instruction is not. 2) As for the acquisition of explicit knowledge, WM plays certain role. High WMC learners benefit more under implicit instruction for their enough capacity to store and process information. While as for low WMC learners, it‘s better for them to get explicit instruction to acquire explicit knowledge because of their limited attention resources. As for the acquisition of implicit knowledge, high WMC learners hold the absolute advantages under explicit instruction, but less lasting effect is showed in the delayed posttest. Meanwhile, due to the hard-to-acquire nature of implicit knowledge, learners can barely benefit a lot under implicit instruction no matter with high WMC or low WMC. These results suggest that WM does play certain role in the acquisition of L2, but it also depends on the explicitness of the knowledge.The study also implicates that different teaching methods with various levels of awareness should be applied to facilitate the SLA. For example, students‘ attention on the explicit knowledge can be enhanced to make full use of the explicit instruction in learning simple syntactic structures. Besides, the combination of the different teaching methods should be applied to the classrooms, to promote the better acquisition of L2 for the learners. On the other hand, with regard to the difference on the WMC, more reasonable teaching plans should be made to meet the different requirements of the students. For instance, more implicit teaching methods can be used for the high WMC learners, and more explicit instruction can be offered to the low WMC learners combined with after class review to enhance the delayed effect.