5Jacob,L. Cooperative learning: Context and opportunities for acquiring academic English[J]. TESOL Quarterly. 1996.
6Sharan. S. Cooperative learning in small group: Recent methods and effects on achievement, attitudes, and ethnic relations [J].Review of Educational Research , 1980.
7Flanigan. O. B. Peer tutoring and second language acquisition in the elementary school[J]. Applied Linguistics. 1991.
8Piaget, J. The Language and Thought of the Child[M]. New York: Harcourt Brace. 1950.
9Vygotsky, L. S. Thought and Language[M]. Cambridge. MA:The MIT Press.1978.
10Hymes. D. On Communicative Competence [M]. Philadelphia.PA: University of Pennsylvania Press. 1972.
