<![CDATA[Critical thinking in EFL speaking can be expressed through questioning and reason-giving during classroom interaction. However, how these speech acts function and can be interpreted as critical-thinking orientations across different communicative contexts remains underexplored. This qualitative case study examined the illocutionary functions of questioning and reason-giving, how they could be interpreted through Facione’s critical-thinking framework, and how communicative demands shaped their emergence in transactional and interpersonal speaking activities. The participants were 46 undergraduate EFL learners. Classroom interactions were recorded, transcribed, and analyzed using Searle’s Speech Act Theory and Facione’s framework, with MAXQDA 2024 supporting the coding and analysis. Of the 230 segments analyzed, 103 involved questioning and 127 involved reason-giving. Information Seeking was the most frequent questioning function (87 occurrences), while Causal Explanation (55 occurrences) and Justification (40 occurrences) were prominent reason-giving functions. In the code co-occurrence analysis, Analysis showed the most intersections, followed by Explanation and Evaluation, whereas Self-Regulation had the fewest. Role-play primarily involved information seeking to address information gaps, while discussion featured defense of argument as learners responded to contrasting viewpoints. Problem-solving prominently involved causal explanation and justification as learners examined problems and considered solutions. These patterns suggest that different communicative demands provided distinct opportunities for learners to express critical-thinking orientations through questioning and reason-giving. Highlights:1. Information Seeking was the most frequent questioning function, while CausalExplanation and Justification were prominent forms of reason-giving in EFL spokeninteraction.2. Questioning and reason-giving reflected different critical-thinking orientations, withAnalysis, Explanation, and Evaluation emerging most prominently in classroominteraction.3. Different communicative demands shaped questioning and reason-giving: role-playaddressed information gaps, discussion engaged contrasting viewpoints, and problem-solving involved explaining problems and supporting solutions.]]>
