Certainty And Systematicity Of L2 Learners' Implicit And Explicit Knowledge

A key issue in the field of second language acquisition has been the difficulty of specifying valid measures of implicit and explicit knowledge. This thesis reviews the literature of implicit and explicit knowledge and gives a critical review to the studies measuring the two types of knowledge through grammaticality judgment test (GJT). Based on previous research, a few modifications are made to the original GJTs designed by R. Ellis (2005). A pilot study was carried out to fix the time limit for the timed GJT for the later study. The results of the study suggest that a timed GJT which requires participants to indicate their comprehension level of the sentences, and then to judge its grammaticality is constructive. The study also examined two hypotheses. First, implicit knowledge is more systematic than explicit knowledge. Second, L2 learners have more confidence in their implicit knowledge than explicit knowledge. The results of the present study seem to support only the first hypothesis. It indicates that L2 learners tend to place more confidence in their explicit knowledge, which may be explained in terms of learnability of implicit knowledge and in-depths development of explicit knowledge in adult L2 learners.