2Kerr, L. English for Sepcial Purposes [ C]//S. Hohen. English for Specific Purposes. Modern English Publications Ltd., 1977.
3Krashen, S. D. The Input Hypothesis: Issues and Implications[ M]. New York: Longman, 1985.
4McDonough, J. Perspective : A Practical Guide[ M ]. London: Collins ELT, 1984.
5Robinson, P. C. Today: A Practitioner' s Guide [ M ]. Prentice Hall, 1991.
6Strevens, P. New Orientations in the Teaching of English [ M] Oxford: Oxford University Press, 1977.
7Strevens, P. After Twenty Years: A re-appraisal[ CI//M. Tickoo. State of the Art. 1 - 13. SEAMEO Regional Language Centre, 1988.
8Swales, J. M. Genre Analysis: English in Academic Research Settings [ M ]. Cambridge: Cambridge University Press, 1990.
9Tarone, E. S. Dwyer, S., Gillete, S. & Icke, V. On the Use of the Passive in Two Astrophysics Journal Papers [J]. English for Specific Purposes, 1981 ( 1 ) : 123 - 140.
10Widdowson, H. G. Learning Purposes and Language Use [ M]. Oxford: Oxford University Press, 1953.