| Code switching has been studied a lot from different perspectives, such as sociolinguistics, conversation analysis, pragmatics, psycholinguistics and so on. The teachers’code switching exists inevitably in the practical teaching and different researchers hold different attitudes on it.To explore the College English teachers’code switching further, an research project was carried out in College English Classroom of Lvliang University using a qualitative and quantitative approach (including classroom observation&recordings, and interviews). This thesis presents the teachers’ code switching situations and attempts to explain the causes of teachers’code switching drawing on the works of Krashen(1985) and Levelt (1989), focusing on two aspects:comprehensible input and the generation of messages.Based on Poplack’s Typology of code switching model, code switching in this thesis are categorized into three types:tag switching, inter-sentential code switching and intra-sentential code switching, and intra-sentential code switching is divided into two types:intra-sentential code switching with L1as matrix language and intra-sentential code switching with L2as matrix language according to Myers-Scotton’s Matrix Language Frame Model.The research findings reveal that College English teachers’appropriate using of code switching in class can serve the functions of explaining teaching contents, helping students’mastering of the relative knowledge, enhancing the comprehensible input of the target language and promoting teaching efficiency, but there are also some unnecessary code switchings. Thus, at last the author tentatively puts forwards some counter-measures: the teachers should set a fair attitude, learn to use code switching appropriately, pay enough attention to students’real needs and develop their own overall knowledge continuously. |