Students in the English as a Second Language (ESL) classroom often use their other languages and semiotic resources (referred to in this study as L1+) to engage with other students in the class. Empirical analysis is needed to understand how and for what purposes the L1+ is used. This study takes a micro-analytic approach using Conversation Analysis (CA) to examine L1+ practices that students engage in and the actions that are accomplished by their L1+ interactions. Data used for the study includes 49 hours of video recordings in an adult community ESL classroom with students at the A2 level according to the Common European Framework of Reference for Languages (CEFR). Microanalysis of the student-student L1+ interactions using a (multimodal) conversation analysis framework reveals three important findings. First, initiation of the use of the L1+ is connected to facilitating understanding among peers and teachers, clarifying, confirming, and responding to the perception of not understanding. Second, L1+ use during language episodes reveals a connection between pronunciation and meaning of lexical items. A struggle with pronunciation is often an indicator of not understanding the meaning of a word. Data suggests that during the language episode, students also use the L1+ for interactional work such as building context, explaining meaning, and explaining the learning process in connection with determining the meaning of a word. Finally, the study reveals L1+ use in a (yes/no) question, answer, and expansion sequence (QAE) pattern, which is often used in the classroom to clarify and discuss classroom procedures and activity instructions. QAE patterns may change as a result of the types of responses that are given, such as affirmative, negative, or in response to the perception of uncertainty. Changing patterns can signify interactional work such as giving accounts and saving face. The data examined and the analysis in this study contribute to empirical research on L1+ student-student interactions in the ESL classroom. The results can be used to inform classroom planning and pedagogy.