abstract the present study deals with a comparison between reactive and pre-emptive focus-on-form in terms of application and efficiency. it was conducted in an intermediate english class in shahroud. 15 male learners participated in this research and their age ranged from 18 to 25. a course book, new interchange 3, and a complementary book were used. every session the learners gave lectures on units of the complementary book and then the teacher taught the course book. in this research, we used a hi-q mp3 voice recorder to record voices during class interactions. we must point out that the teacher recorded the whole time of class, but we just addressed the conversations between the teacher and the learners. two kinds of data sheets were utilized to collect raw data, one for registering ffes and the other one for registering uptake episodes. in fact, they were used for counting episodes. for analyzing the data, chi square test (?²) and phi coefficient (?) were used. the results of the data analysis demonstrated the superiority of pre-emptive over reactive in terms of application and efficiency according to exact statistics and valuable findings which arose from direct observations. so vocabulary, grammar and pronunciation as indispensible elements of speech under the linguistic coverage category were our variables in the study which accepted the influence of focus-on-form to render service to language improvement. key words: focus-on-form; reactive; pre-emptive; focus-on-form episodes (fees); uptake; linguistic coverage