Roshan, Saeed2023-08-012023-08-012021Konińskie Studia Językowe: Konin Language Studies, ISSN: 2353-5148 (Print); 2353-5148 (Online), 9(4), 435-454.2353-51482353-5148http://hdl.handle.net/10292/16491This article presents the findings of a study investigating the effectiveness of four types of written corrective feedback (i.e., direct corrective feedback, direct corrective feedback plus revision, metalinguistic explanation, metalinguistic explanation plus revision) on a complex linguistic structure, the English passive voice. The study was undertaken with 100 university students with a pre-test, treatment, immediate and delayed post-tests design. The findings showed that a single episode of written CF improved accuracy immediately and over time for all the experimental groups, but not for the control group. They also revealed that direct CF led to more improved accuracy compared to the other experimental groups. The results of this study contribute to our understanding of how written corrective feedback works and validate aspects of Gass’s (1997) cognitive processing model and skill acquisition theories (DeKeyser, 2015) for the written context.Journal ArticleOpenAccess