7Dickinson L. Autonomy and motivation: a literature review [ J]. System, 1995.
8Holec H. Autonomy and Foreign Language Learning [ M ]. Oxford: Pergamon Press, 1981.
9Moore M. Three types of interaction [J]. The American Journal of Distance Education, 1992,3, (2).
10Paramskas D M. The shape of computer-mediated communication [ A ]. In Keith Cameron(ed. ). Computer Assisted Language Learning(CALL) : Media, Design and Applications[ C]. Lisse(Netherlands) : Exton, PA:Swats & Zeilinger, 1999.