The effect of task type on interlanguage pragmatics development has remained under-researched. This study aimed to explore the effects of an input-based task (i.e., consciousness-raising task) and an output-based task (i.e., discourse completion task) on learning the speech act (SA) of suggestion. To this end, sixty Iranian EFL ninth graders were selected as the participants of the study through convenience sampling. Then, they were assigned to three non-equivalent groups (i.e., one control group and two experimental groups). A 10- item scenario-prompted written discourse completion test (WDCT) was administered as the pretest and posttest to all three groups. Afterward, the input-based group received the target SA, enhanced with colored bold-face subtitles, and output-based group received the same clips with regular subtitles and were asked to do WDCTs. The control group was taught through a traditional instructional procedure with the same clips. Finally, they sat for an immediate posttest. The results demonstrated that input-based task had the most significant within-group effect on learning the target SA from the pretest to the posttest, followed by output-based task and traditional instruction. At the same time, no statistically significant differences were found among the groups' posttest performance. The implications are offered finally. تفاصيل المقالة