6[2]Coleman,H.Learning and teaching in large classes[J/OL].From http://www.hywelcoleman.com/learning.htm.2002.
7[3]Huitt,W.Humanism and open education[J/OL].Educational Psychology Interactive.Valdosta,GA:Valdosta State University.From http://chiron.valdosta.edu/whuitt/col/affsys/humed.html.2001.
8[4]Krashen,S.Fundamentals of Language Education[M].Torrance,CA:Laredo,1991.
9[5]Long,M.H.Input and second language acquisition theory[A].In S.Gass and C.Madden (eds.).Input in Second Language Acquisition[C].Rowley,MA:Newbury House,1985.
10[6]Jacobs,G.and J.Ball.An investigation of the structure of group activities in ELT course books[J].ELT Journal,1996,50(2):99-107.