With the emergence of sociolinguistic approach in second language learning, instructors have begun to acknowledge the native language (L1) as a legitimate tool with the potential to facilitate second language (L2) learning mainly in output-based tasks. This study focuses on how the use of L1 by L2 learners affects their task achievement. Two communicative tasks were used, and tasks were carried out by 32 high school students in L2 only, or in L1 and L2 during group test sessions held on different days. Tape-recorded transcripts of learners when performing the tasks, interviews, and questionnaires were collected and analysed to investigate effect on the use of L1. The findings suggest that during performing the tasks, learners used their L1 to complete their tasks for a variety of functions. Through the L1, they explained and negotiated the task each other, or checked their understanding or compared answers to the task against their peers. To allow the learners to use of their L1 was even more effective than to urge them to use L2 only in a foreign language class using task. Further investigation indicates that, if one of goals of output-based introduction is considered as the successful completion of the task, the learners’ use of L1 may be beneficial to attain the goal when performing completely in L2 is impossible or beyond the learners’ linguistic ability.

Abstract
Ⅰ. Introduction
Ⅱ. Literature Review
Ⅲ. Methodology
Ⅳ. Results and Discussions
Ⅴ. Conclusion
References
Appendix
저자소개

• Mong Ju Lee(University of Newcastle, UK) | 이몽주