Unaccusative and Unergative Verb Acquisition: Effects of Implicit, Explicit, and Mixed Oral Corrective Feedback

Persian L2 learners of English over-passivize the unaccusatives. Therefore, it is necessary that teachers identify erroneous over-passivization of unaccusatives and provide the necessary explanation of the differences between unaccusatives and unergatives. Issues such as type of instructions provided by teachers in the Second Language Acquisition (SLA) classrooms still suffers from unanswered questions. This study focused on the acquisition of the differences between unaccusatives and unergativesby intermediate and advanced learners before and after receiving oral Corrective Feedback (CF). 106 students who scored 1 standard deviation below and above the mean score of the quick Oxford placement test (SD= 6.11, mean= 36.94), and also the WEPT and GJT were administered as the post-tests. The results revealed that while students had the ability to judge the grammaticality of the sentences with unergatives before receiving oral CF, they did not have such ability for sentences with unaccusatives, and it was only after receiving the oral CF when they acquired the required knowledge.