l • ..... ,'! . . . • t • .. • . . ' ... Thi§ quasi-experimental study endeavored to identify the corrective feedback strategy that was most effective in enhancing the learners' oral interaction in EFL classes. In doing so, the researcher examined whether or not there existed significant oral interactive performance differences among groups of students who received teacher-led feedback, peer feedback, self­ corrective feedback and teacher-led explicit instruction, and the particular techniques employed and/or favoured by the teacher and/or by the learners during the teaching-learning process. To this end, a quasi-experimental design was employed. The participants of the study were grade 9 students in Bahir Dar Zuria Woreda General Secondary School. 158 participants were selected using convenience sampling method for the first 3 experimental groups and a lottery method for the teacfier-centered instruction group. They were then assigned to the four treatment groups, each of the first 3 experimental groups comprising 40 members and the fourth experimental one consisting of 38 members. Pre-test, followed by 6 session oral interactive lessons, and then post­ /est were administered. To collect data in all these respects, the pre- and post-tests and the recordings of the whole process of the lessons were employed. The data were analyzed quantitat,ely using a one way ANOVA for the pre- and post-tests and a frequency analysis for the lesson recordings. The results of the study computed by the one-:-way ANO VA revealed that there were significant aggregate mean score differences among the four groups of students, the peer corrective feedback treatment group having the highest score. However, the findings of the Bonferroni 's method of six pair wise comparisons revealed that the mean score differences between the peer corrective feedback and the teacher-centered instruction, and the peer corrective feedback and the teacher-led feedback treatment groups were the only statistically significant ones among the six comparisons, the peer feedback treatment group outperforming the two groups. Hence, it was possible to conclude that the provision of peer corrective feedback J ABSTRACT vii .i is the most effective strategy that helps students to enhance theiroral interaction. The frequency analysis, on the other hand, showed that the teacher in teacher-led feedback employed all the six feedback techniques with the highest frequency of the elicitation technique(n=52), which was also found to be the particular technique favoured. The learners in peer feedback also used all the feedback techniques except recasts, and elicitation (n=43) and explicit correction (n=41) were the most frequently used/or favouredtechniques. In the self-corrective feedback treatment group, recasts (n=37) and explicit correction(n=19) techniques were tbe only ones used, recasts being ., the technique favoured. The elicitation and the explicit correction feedback techniques, which were the most frequently employed feedback techniques in the peer feedback treatment group, .. might have helped the learners to outperform the other groups of students. Finally, based on the findings, some possib~gestions were recommended to EFL teachers, students, responsible authorities and training institutions, material writers and other researchers