This study investigated the use of L1(English) by L2(Korean) learners’ interaction with their native-speaking conversation partners from a sociocultural perspective, using the lens of conversation analysis. The data included 64 hours of recorded interactions of 16 conversation pairs of nonnative learners of Korean and their native conversation partners as well as learners’ diary entries. Findings gleaned from qualitative analysis of learners’ use of their L1 (i.e., English) during native-nonnative pair interactions outside the classroom showed that the overall use of L1 by L2 learners found to be facilitative of their L2 learning. The results proposed a model of L2 learners interaction with their conversation partners that attempted to link learner’s use of L1 and their L2 proficiency, and concluded that learners’ interactions played a key role in improving L2 learners’ language proficiency. In addition, pedagogical recommendations based on the research findings were proposed.

I. Introduction
II. Theoretical Background
    1. Sociocultural Approaches to Interaction
    2. Native and Nonnative Speakers in Language Learning
    3. L1 use in L2 interaction
III. Methods
    1. Participants
    2. Data Collection and Analyses
IV. Results & Discussion
    1. Learner’s Linguistic Competence and Performance
    2. The Asymmetric Roles of Speakers
    3. L1 Use for Clarification/Confirmation/Assurance
    4. Prior Acquaintance with CP
    5. CP’s Motivation to Speak Learner’s L1
V. Conclusion
References

• Jeongyi Lee(Department of Foreign Languages Kennesaw State University)
• Keun Huh(Department of English Language & Literature Hannam University) Corresponding author