LAUSR

This study employs Critical Discourse Analysis (CDA) to examine the dynamic negotiation of identities and power dynamics among two English-as-the-first-language (L1) and two English-as-the-second-language (L2) teachers in an undergraduate English-as-a-foreign-language (EFL) co-teaching program in China. Data consists of 980 min of audio/video recordings from in-class co-teaching sessions, collaborative lesson-preparation meetings, and group interviews. The analysis integrates Fairclough’s modality framework and van Leeuwen’s legitimation strategies to examine how identities are negotiated in real-time interactive discourse. Findings reveal that co-teachers fluidly adopt multiple identities—mutually supportive facilitators, willing-to-compromise negotiators, experts and learners in EFL teaching, and self-recognized qualified evaluators—through moment-to-moment discursive practices shaped by power equilibrium and disequilibrium. Notably, the study captures how authority shifts contextually based on situated expertise, challenging rigid L1 to L2 dichotomies. A key contribution lies in its methodological innovation: by prioritizing real-time discourse over retrospective narratives, the study unveils the immediacy of identity negotiation, offering granular insights into how teachers strategically position themselves and resist marginalization. The findings underscore the need for co-teaching models that valorize teachers’ complementary strengths, advocating for professional development programs that foster critical reflexivity and equitable collaboration in multilingual contexts.