To contribute to this line of research, the present study aimed at investigating the effect of deductive and inductive instruction on the development of the speech acts of requests by Iranian EFL learners. In so doing, 51 Iranian EFL English-major students were randomly assigned to either the deductive group (DG) group (n = 24) or the inductive group (IG) group (n = 27). (IG). Both groups were provided with video clips of short conversations including the speech acts of request. The experimental treatment for the DG followed explicitness and deduction accompanied by a variety of drills, whereas the instruction for the IG involved input enhancement techniques. Both deductive and inductive methods of instruction adopted in the present study were operationalized according to the principles underlying the paradigms of Focus on Forms (FonFS) and Focus on Forms (FonF). Speech act development of the two groups was measured through a 10-item Written Discourse Completion Test (WDCT) at the pre-treatment and post-treatment phases of the study. The results obtained from administered WDCT revealed that both deductive and inductive instruction had a significant effect on the learners’ development of requests. Further analysis of the findings revealed that inductive instruction was more effective than deductive instruction. The findings offer theoretical and pedagogical implications.
