Effects of Input-based and Output-based Instructions on Iranian EFL Learners’ Productive Knowledge of Collocations

Few studies have investigated the effects of input-based and output-based instructions on collocational knowledge of EFL learners. Therefore, this study aimed to examine the effects of these instructional approaches on Iranian EFL learners’ productive knowledge of collocations. To this end, 80 senior high school students from three intact classes at Tali-e High School in Ahvaz, Iran, were selected. Each class was assigned to a control group (n = 28) and two experimental groups including the input group (n = 27) and the output group (n = 25). Twenty collocations were selected as the target collocations. Then, a pretest was administered to all groups. Two days after the last treatment session, an immediate posttest was given to the participants. A delayed posttest was also administered two weeks later. The results of Mixed-ANOVA, one-way ANOVA, and Tukey post hoc tests revealed that both input and output groups outperformed the control group on the immediate and delayed posttests. However, there were no significant differences between the input and output groups on the posttests. The implications and suggestions for future research are also presented.