5[6]Ellis,R.The Study of Second Language Acquisition[M]. Shanghai: Shanghai Foreign Language Education Press.2000.
6[7]Mclaughlin, B.Theories of second-language learning.London:Edward Arnold.1987.
7[8]Corder,S.P.Language-learner language, In J.Richards (Ed).understanding second and foreign language learning: Issues and approaches.Rowley,Mass,:Newbury House.1978.