Abstract:
This study investigates whether the effectiveness of immediate and delayed corrective feedback in task-based instruction varies as a function of L2 learners' proficiency level． 120 EFL learners at a Chinese middle school were divided into high and low proficiency levels based on their mid-term exam scores． At each proficiency level， the learners were further divided into four groups: immediate feedback，delayed feedback， task-only，and control． The experimental groups performed two dictogloss tasks where they received the teacher's immediate feedback，delayed feedback or no feedback on their wrong use of the English passive voice． The results showed that ( 1) immediate feedback was effective for low-proficiency learners while delayed feedback was not，( 2) high-proficiency learners benefited equally from immediate and delayed feedback，and ( 3) task-only facilitated highproficiency learners' L2 development but it was not effective for low-proficiency learners． These findings demonstrate the superiority of immediate feedback and the usefulness of communicative tasks for high-level learners． We attribute the disparities between the effects of the two feedback types to the different cognitive demands imposed on learners rather than the timing of feedback． Key words: feedback timing; immediate feedback; delayed feedback; L2 proficiency; task-based language teaching
