Research Procedure
After the investigation, all the discourses of the teachers and their students were transcribed and calculated from the three aspects: the amount of teacher talk, the types of discourse structure, the uses of teachers’ questions. The process of data collecting, transcribing and calculating is exhausting, as it needs patience and great care. All the items (of three times of audio-recording of each class) concerning the above three aspects were counted to get the means and average percentages of the items for each class. The means and average percentages of the items of the four classes were finally calculated and