The present study aimed at investigating the effects of the two types of teacher feedback―direct corrective feedback (DCF) and metalinguistic explanation (ME)―on the development of EFL learners’ knowledge of the English indefinite article and on their use of it in writing. For this study, 58 college students classified into three groups (two experimental groups and one control group) took the error correction test and performed three writing tasks. The results of the study are 1) there was no group effect of the two types of feedback in the development of their explicit knowledge of the target feature in the test, whereas a time effect was found that their knowledge of the target feature developed significantly after the treatment; and 2) no group differences were found between the two types of feedback in the use of the target feature in the revised writing and among the three writings, though the DCF group outperformed the ME group in the accurate use of the target feature in writing. Theoretical and pedagogical relevance of the findings is addressed.

The present study aimed at investigating the effectiveness of bottom-up (BU) and top-down (TD) approaches on EFL learners’ vocabulary learning, the difference in the effects of the two approaches depending upon their level of vocabulary proficiency, and their perception of the approaches. For this study, 122 college students were divided into two approach groups and to two levels in each group depending upon their level of vocabulary knowledge. They were trained with either of the approaches for one semester. The results were that 1) there was no statistically significant differences between the BU and TD approaches, even though the two approaches were effective to improve the students’ vocabulary knowledge; 2) high-level students failed to show any significant differences between the two approaches in the two tests, whereas low-level students in the BU group performed significantly better than those in the TD group in the production test; and 3) they preferred the BU or TD approach to the traditional method in vocabulary learning, and they listed some advantages and disadvantages of the approaches.