| Practical reasoning has always been thought as the main factors in teachers’ reasonable action and good teaching. Although some related studies have been done, these studies were impractical philosophizing and ignored the specific nature of situation of classroom teaching. This study aims to describe the actual process by a careful analysis of primary school beginning teachers’action, reveal influencing factors, illustrate the features of teachers’practical reasoning, and then develop some potential suggestion for the improvement of teachers’practical reasoning.Practical reasoning means a person’s logical thinking when making an action in a specific situation. With 6 primary school beginning teachers and 55 critical incidents among 27 lessons of these teachers selected as data sources, this study attempts to depict the whole picture of practical depending on the interview materials and ethnographic field notes. This study found that, (1) Teachers’practical reasoning mainly presents sufficient condition schemata, which means that teachers have sufficient reason to do something for a goal, but this kind of action is not the only solution to achieve this goal; (2) There are many kind of premises which constitute practical reasoning, the empirical premise which takes four forms (generalizing inferences, explanatory inferences, researches on teaching and hypothesis about the future) is most widely. (3) Teachers’ practical reasoning mainly presents "Reason-evidence" structure, namely, teachers inclined to raise a course of action first and then look for reason to support this kind of action. (4) Subjective, structural and situational factors are all the influencing elements of practical reasoning in classroom teaching. Subjective factors involves teachers’focus, responsibility, patience and independence; Structural factors include time-task structure, organization-culture structure and family-society structure; the situational factors were reflected in the difference of practical reasoning between management problems and teaching problems, between personal situation and group situation.There are some obvious uniqueness of teachers’practical reasoning. First, good teachers’ practical reasoning was required to reflect comprehensive values like justice and care and plays an important role in cultivating students’rational thinking and moral virtue. Also, due to the Irreversible time structure and the missing data and peers’ participation, teachers’ practical reasoning might been simplified. To improve teacher’s practical reasoning, first teacher should become a good practical reasoner by electing and reconstructing their practical arguments and then change the current teacher education model. |