1Lemake, J.L. Using Language in the Classroom [M]. Geelong, Australian: Deakin University Press,1985.
2Skehan, P. Second Language Acquisition Research and Task Based Instruction [A]. In J.Willis & D. Willis (eds.). Challenge and Change in Language Teaching [C]. Oxford: Heinemann,1996.
3Stevick, E.W. Memory, Meaning and Method: A View of Language Teaching [M].Boston, MA: Heinle &Heinle ,1996.
4Swain, M. Communicative Competence: Some roles of comprehensive input and comprehensible output in development [A]. In S. Gass & C. Madden (eds). Input in second language Acquisition [C]. Rowley, Mass: Newsbury House, 1985.
