Many studies claimed that teachers are influential in classroom from the perspective; the human beings present in the classroom interact in a complex context to which students are susceptible in many aspects of learning. Especially in language classrooms, teachers are assumed to be more important and influential, which means that a teacher can play a greater part in helping the students to learn the language. Thus, it is worthwhile to focus on teachers in the classroom. The purpose of this study is to explore what two effective ESL teachers do in the classroom. Three different qualitative techniques were used and some salient findings emerging were used as themes. For data, the teachers" teaching was observed in class and they were interviewed outside of class. Students" responses to the teachers" behavior through written diaries and interviews were gathered to triangulate the data, which helped to yield more valid and comprehensive viewpoints. This in-depth examination of the two teachers allows us to better understand teacher roles in terms of encouraging students" better learning behavior in the classroom. It was found that, besides the two teachers" technical attention to teaching purposefulness, their attention to affective factor seems to be also effective.