An Empirical Study On The Effects Of Lexical Chunk Teaching On Senior High School Students' English Writing

New Curriculum Standard makes writing ability more and more important.The study of Engber(1995)finds that the lexical richness in English writing has positive effects on writing quality,so it has great significance to study lexical richness in English writing.However,the present studies pay much attention to the number or types of lexical chunks or emotions(Li,2012;Fu,2015;Yao,2016 etc.).Based on the Information Processing Theory,Interaction Theory of Second Language Acquisition and Dynamic Systems Theory,it aims to explore the effects of lexical chunk teaching on writing scores and lexical richness(lexical variation,lexical sophistication,lexical density).The research adopts experiment and case analysis methods.The experiment class is taught with lexical teaching while the controlled class with traditional vocabulary teaching method.A pretest and a post-test are conducted among all subjects before and after the experiment.And all the writings are processed by Range 32 to get all the data about lexical richness,then these data are analyzed with SPSS20.0.The results of this study are as follows: first,lexical teaching can improve students' writing scores.Second,lexical teaching increases tokens,types and lexical variation;lexical teaching decreases the words from Baselist 1 and Baselist 2;Baselist 3 words and “not list words” increase significantly,which greatly increases lexical sophistication;at the same time,lexical teaching almost has no significant effects on lexical density.Thirdly,case analysis is conducted to make a comparison between lexical teaching and traditional teaching method,then some advantages and disadvantages of both methods are concluded.Finally,some suggestions about the application of lexical teaching methods are put forward.