Explicitness in CALL feedback for enhancing advanced ESL learners' grammar skills

Due to technological advances utilized in academia, international students at U.S. colleges and universities are now challenged with more opportunities to write while taking courses. Instructors, for example, increasingly utilize online course management systems that offer enhanced methods of participation in class discussions. International students are often required to take English as a Second Language (ESL) writing courses to improve their academic writing skills. However, these courses typically focus on content and style with less emphasis on grammatical accuracy.;Thus, the development and use of an online tutorial that delivers different types of feedback and helps students become better editors of their own writing may play an important role in international students' success in their academic life. Consequently, the purposes of this research were to (a) examine the effectiveness of the types of feedback that vary in its explicitness in a computer-assisted language learning (CALL) environment, and (b) examine adaptive methods of feedback delivery based on learners' performance. Both issues were examined within the context of a computer-based tutorial designed to help advanced Korean learners of English reduce overpassivization errors in academic writing. Utilizing a pretest, posttest, and a delayed posttest design, repeated-measures ANOVA and descriptive analyses were conducted. The results suggested that among the types of corrective feedback provided (traditional, prompt, contrastive, and adaptive), the contrastive type of feedback---which contained the target structure and the student's L1 translation with the passive morphemes visually highlighted in both languages---seemed to be the most effective feedback type for increasing the adult Korean ESL learners' ability to recognize and correct overpassivization errors.