This study investigates the effects of input-based and output-based instructions on the acquisition of second language (L2) request modifiers. Four intact classes were randomly assigned to textual enhancement (TE), input flooding (IF), output-based instruction (OI), and control (CO) groups. The TE group watched some captioned videos on requests and read over the video transcripts with the target features typographically highlighted. The IF group watched twice more captioned videos and read over the video transcripts with no textual manipulation. The OI group watched videos with no captions and then engaged in dialogue reconstruction tasks. Results of the pragmatic comprehension and production pre-test and post-test revealed the overall effectiveness of the treatment. TE and OI groups performed rather similarly in the comprehension test. Concerning the production test, the OI group performed best, followed by TE, IF, and CO groups. The findings suggest employing input-based and output-based practices to promote learners’ L2 pragmatic knowledge.
