| Halliday’s systemic functional linguistics has three meta functions:concept function, interpersonal function and textual function. The realization of each function has a form of grammatical metaphor. In the framework of systemic functional linguistics, grammatical metaphor has the concept of grammatical metaphor, interpersonal grammatical metaphor and textual grammatical metaphor. Among them, the interpersonal grammatical metaphor and grammatical metaphor can be divided into tone and modality of grammatical metaphor. Based on the modal orientation, type and function of metaphor, this paper expounds the basic knowledge of the modality and usage, and reveals the importance of modality in interpersonal grammatical metaphor. Oral English teaching holds an important place in English teaching, And lots of modality in communication is a big cause of oral English communication difficulties. Through Xinyang NO.1Senior Middle School and Xinyang NO.9Junior Middle School’s two English teachers classroom observation and recording, conducted a questionnaire survey of its class of students, and interviews with two of the high school to investigate and analyze oral English. Combining with specific examples how discourses analysis of modality comprehension difficulties, explore the interpersonal grammatical metaphor to the guiding role of reading comprehension, and provide an idea for oral English teaching. In this paper, the author discusses the modality metaphor theory and the relationship with college English teaching, planed and orderly way to modal metaphor introduced the teaching experiment, by comparing the experimental data, obtained the modality metaphor teaching is introduced in the oral English teaching, can effectively improve students’ oral English communicative ability, I hope this can arise the attention of middle school English teachers. |