本文旨在探讨高中英语老师与学生在任务型语言教学法中所扮演的特殊角色，以及试图找出可以帮助老师和学生做得更好的方法。本研究采用的研究方法有课堂观察法、问卷调查法、Excel和SPSS数据分析方法。通过对有效数据的详细分析，本研究主要发现，与传统的教学方法相比，教师和学生在任务型语言教学课堂中的不同阶段扮演着不同的角色。在前任务阶段，教师是引导者、组织者、解说者和示范者，学生是听众，观察者和任务规划者；在任务阶段，教师是辅助者、评价者、参与者，学生是实践者、组织者、合作者、表演者和问题发现者；在任务后阶段，教师是监督者，学生是自我评价者和评价者。进而得出教师在教学活动中的教师观和学生观、学生对自己的定位以及师生关系影响着教师和学生的角色扮演这一结论。因此，改变教学活动的教师观和学生观、帮助学生进行较好地自我定位、改善师生关系是教师和学生在任务型语言教学课堂中扮演好各自角色的关键因素。

The purpose of this study is to explore particular roles of Senior High School teachers and students in a task-based language teaching course and to try to find out the way to act better. The research approach adopted in this study includes classroom observation, questionnaire, Excel analysis, and SPSS analysis. By detailed analyses, the main findings from this research provide evidence that teachers and students have different roles in various stages of a TBLT course from a traditional one. In pre-task stage, teachers act as guider, organizer, expositor and demonstrator, and students act as listener, observer and planner. In while-task stage, teachers act as helper, evaluator, participant, and students act as practitioner, organizer, collaborator, performer, problem discoverer. In post-task stage, teachers act as supervisor, and students act as self-evaluator and evaluator. Moreover, it is the view of teachers and students in teaching activities, students’ orientation to themselves and teacher-student relationship that affect teacher and student’s roles. Therefore, changing the view of teachers and students in teaching activities, helping students to better self-positioning, and improving the relationship between teachers and students are the key factors for teachers and students to play good roles in a TBLT course.