Abstract-This study was set up to investigate whether various Focus on Form techniques facilitate L2 grammar learning. The study involved a pre-test─post-test design with treatment and control group and attempted to examine the relative effectiveness of three focus on form techniques, i.e. input enhancement, output and collaborative output, on learning English passive forms. Forty-four Iranian learners of English were selected to participate in the study. The participants were assigned to one of the four groups consisting of input enhancement (IE) (n=11), input enhancement together with individual text-editing task (IE+TE) (n=11), input enhancement together with collaborative text-editing task (IE+TE+CO) (n=12) and a control group (CG) (n=10). The pretests and posttests were administered using a multiple choice and a fill in the blank test in context. The result of the study showed that among the three treatment groups, IE+TE and IE+TE+CO outperformed the control group in the acquisition of passive forms. Furthermore, there was no significant difference between IE+TE and IE+TE+CO in the acquisition of passive forms.