(1) In the classroom, the common roles teachers play include organizer, prompter, participant, resource provider and assessor.
(2) To play these roles appropriately in a learner-centered classroom, there are many requirements and expectations for the teachers. First, the most important and difficult role that the teacher has to play is to be an organizer. One of the teacher’s major tasks is to design and organize tasks that students can perform in the class. As an organizer, the teacher should use creative and unlimited way; envisage activities; anticipate the problems; give clear and concise instructions; demonstrate; use native language to clarify if necessary; walk around and monitor; rectify; take mental notes. Second, as a prompter, when students are not sure how to start an activity, or what to do next, or what to say next, the teacher should give appropriate prompts by giving hints just like time, place, etc. and eliciting more by saying “and...?” “Anything else?” “Yes, but why...?” Third, as a participant, the teacher should participate in students’ activities and shouldn't dominate or appear to be authoritative. Fourth, as a resource provider, the teacher is considered as a good and convenient resource for the students, but the teacher should withhold his/her readiness to provide resources. Last, after class the teacher is an assessor, who evaluates not only how successfully he/she has conducted the class but also how efficient the learning activities have been.
(3) Therefore, it should be noted that teachers’ roles are not static. They change in the different stages of the teaching processes and they change with the development of the society, thus it is important for teachers to play different roles for teaching purposes.