摘要：The present study sought to investigate the effect of explicit instruction (direct proactive explicit instruction) on the acquisition of English passive objective relative clauses. Two groups of participants were involved in the study; a group of advanced EFL learners (n = 16) and a group of intermediate EFL learners (n = 37) who were randomly divided to two groups of experimental (n = 22) and control (n = 15). The experimental group received 4 sessions of explicit instruction on the target structure. The control group, however, did their routine activities in a writing class. There were three test times, namely a pre-, post-, and delayed post-tests. Two separate measures of explicit and implicit knowledge were applied; an offline test of metalinguistic knowledge (an error correction task) and two online speeded tests of implicit knowledge (a self-paced-reading task and a stop-making sense task). The findings revealed a positive effect of explicit instruction for both implicit and explicit knowledge for the treatment group. Durable effects of explicit instruction were found based on the results obtained from the delayed post-test. The advanced group performed very closely to the treatment group, indicating the effect of explicit instruction in accelerating language learning, as well as the necessity of explicit instruction for some language forms to be acquired in EFL contexts. Keywords: Explicit/explicit instruction; implicit/explicit knowledge; online/offline tests; English reduced relative clauses
