s action research study intended to examine (1) whether students? critical thinking in  writing  exposition  text  is  enhanced  through  questioning and  (2) the general description about the implementation of questioning in the classroom to enhance students? critical thinking in writing exposition text. The subject of this study was all students of semester I, semester III, and semester V (10 students) in a private foreign language academy.
The duration of the study was approximately 2 months consisted of 12 one- hour Writing lectures. There were 3 spirals of self-reflective cycles implemented and each cycle consisted of four meetings. Each meeting in a row was planning, acting, observing, and reflection.
The data collected were qualitative (through observation and interview) data analyzed by using Constant Comparative Analysis method and quantitative data (in the form of writing exposition text scores) from the mean scores of pre-test and post- test. When the lecturer-as-researcher gave the treatment, the students were taught to ask questions to determine arguments for their exposition texts. Therefore, the results revealed that the critical thinking of the students in writing an exposition text was enhanced by implementing questioning