Teacher questioning is crucial for fostering critical thinking in English as a Foreign Language (EFL) classrooms. Understanding how teachers use critical thinking questions is essential for researchers and practitioners seeking to enhance students' critical thinking skills. This study draws on the Paul-Elder Critical Thinking Model and the Initiation-Response-Feedback questioning interaction model to examine the frequency, strategies, response modes, and feedback standards of critical thinking questions used by senior high school EFL teachers in China. The study involved six EFL teachers and employed classroom observations and interviews as primary data collection methods. Key findings indicated that critical thinking questions accounted for a small proportion of all questions posed in EFL classrooms, with varying emphasis on different critical thinking elements. Repetition was the most commonly used questioning technique, while nominating was the predominant response mode. Feedback on students' responses primarily focused on clarity. The study offers practical implications for designing questioning strategies to enhance students' critical thinking skills.