7Wallace, M. J. Teaching Vocabulary [ M ]. London: Heinemann Educational Books, 1982. 27.
8Laufer, B. & I. S. P. Nation. Vocabulary Size and Use:Lexical Richness in L2 Written Production [ J ]. Applied Linguistics, 1995, (3) :307 - 322.
9Laufer, B. The Development of Passive and Active Vocabulary in a Second Language: Same or Different? [J]. Applied Linguistics, 1998, (2) : 255 -271.
10Coady, J. L2 Vocabulary Acquisition: A Synthesis of Research [A]. In Coady,J. and T. Huckin (eds.). Second Language Vocabulary Acquisition: A Rationale for Pedagogy[ C ]. Cambridge, UK: Cambridge University Press,2000. 273 - 290.
