Although substantial research shows the effectiveness of written corrective feedback (WCF) in treating simple grammar structures, more research is still needed to refute Truscott’s claim that WCF may not work on complex grammar structures. Similarly, a previous body of research has shown that the degree of explicitness of feedback moderates the efficacy of WCF. However, most WCF studies have systematically manipulated only direct corrective feedback. The current study was therefore conducted to fill these gaps in the literature. To this end, five intact classes of Functional English were recruited and later randomly assigned to four treatment groups: DCF, DCF+ME, ICF, and ICF+ME, and one control group that received no feedback. All the groups took part in three WCF treatment sessions, during which they wrote two different pieces: a news report and a picture description. Later, only the treatment groups received the WCF. The WCF’s effectiveness was measured by writing tests and grammaticality judgment tasks (GJT). The results demonstrated that WCF helped L2 learners improve their grammatical accuracy of passive voice tenses. The study further showed that the group that received the most explicit type of WCF fared better than the ones that received the least explicit type of WCF. Important pedagogical implications for ESL/EFL teachers are discussed.

direkte korrektive Rückmeldung; indirekte korrektive Rückmeldung; metalinguistische Erklärung; passive Stimme