A Comparative Analysis On The Effects Of Explicit And Implicit Grammar Instruction In Junior High School

English grammar is an inseparable part of English teaching in middle schools. With the deepening of the English teaching reform and the implementation of communicative language teaching, the major problem of grammar teaching is no to teach, but how to teach. At present, the time spent on grammar teaching in middle school is far less than that before, therefore, how to teach English grammar in an effective way in an limited time becomes necessary. This thesis is to explore the two different instructions in classroom circumstance, namely the explicit instruction and the implicit instruction, and try to find out which instruction is more advantageous to learn English grammar and maintain for junior high school students.As to grammar teaching, there exist two main representative approaches: explicit grammar instruction and implicit grammar instruction. The two rival claims on grammar teaching stem from the opposed theories of Krashen and Schmidt on the role of explicit and implicit learning in SLA.Krashen(1981, 1982,1985, 1992) claims that second language acquisition largely resulted from unconscious acquisition processes and that unconscious acquisition is superior to conscious learning. While Schmidt(1990, 1994,1995, 2001) holds that conscious at the level of noticing is necessary for the second language learning and that consciousness at the level of rule awareness is strongly facilitative of language learning. Based on this,the study proposes the three following question:1) Do implicit instruction and explicit instruction have different effects on the learning of the simple future tense?2) If yes, which instruction is more effective on the learning of form, meaning and use of the simple future tense?3) Which instruction has a long-term effect on the learning of the simple future tense?The subjects involved were 62 students in Dachuan junior high school in Xigu district of Lanzhou.They were divided into an implicit group and an explicit group, with 31 students in each group. An independent samples t-test was used to find out there is no significant difference between two groups in the overall English proficiency before the experiment. Two groups teach the target grammar respectively under two different conditions. The research target grammar is the simple future tense.The subjects took part in the test 3 days and 4 weeks after the treatment respectively: the immediate grammar test and the delayed grammar test. The two tests respectively investigate the subjects on the learning and maintain of the targetgrammar.Relevant data was analyzed by using SPSS software package 13.0. The results showed that the explicit group demonstrated significantly better performance than the implicit group both in the posttest and in the delayed posttest. Both the implicit group and explicit group in the delayed posttest after 4 weeks were lower than those in the post-test, and explicit group showed no significant differences, but implicit group showed significant difference, which indicated that explicit instruction has a long-term effect on the target grammar. These results confirmed Schmidt’s hypothesis and contradicted with Krashen’s hypothesis.The study provides useful insights into our understanding of explicit instruction that is of pedagogical significance to EFL instruction.