The vitality of teacher response to students' writing is not only undeniable (Ferris, Pezone, Tade & Tini, 1997) but also as Coffin et al. (2003) believe, is a central pedagogic practice. Despite the existence of studies in the area of written teacher commentary (Bowen, Madsen, & Hilferty, 1985; Cohen, 1987; Doff, 1990; Fathman & Whalley, 1985; Ferris, 2002; Frodesen, 2001; Rieken, 1991; Zamel, 1985), there are still doubts about the most effective types of teacher feedback. The purpose of this study is to investigate the efficacy of three most prevalent error treatment techniques directive (explicit), partial (researchers’ terminology), and general feedback. To accomplish the expected goal, three groups of female students with intermediate level of proficiency were selected and the written errors of each group were treated according to one of the feedback techniques during the course of study. The analysis of the students' scores revealed that students receiving the directive feedback, improved significantly in comparison with those in the other two groups.