This study aims to investigate the effect of reformulations as an indirect technique of feedback on the improvement of the use of prepositions in Iranian EFL learners' writing in two different contxts of hish schools and English private institutes and to find the extent of differences between male and female learners' improvement in the use of prepositions. The study was conducted due to the importance of the concept of feedback in language learning acording to many scholars. For this aim, eighty students from four state high schools including 40 girls and 40 boys were selected and divided into two groups of experimental and control with twenty participants each and sixty language learners from one English private institute including thirty girls and thrity boys. The procedure of data collection included assigning four writing tasks with similar pre-determined topics to the prticipants. Reformulation was used as a feedback for the experimental group and no feedback was used for the control group. The data of the study were analyzed using ANOVA. The results indicated that reformulation has no sognificant effect on the improvement of the use of propositions and can neither help male and female EFL learners develop their general writing abilities in both contexts.
