Critical Period Hypothesis 这是你论文需要的theory.可以在维基搜索到相关资料.这里不可以提交这个网址 :( 参考文献： The Influence of Age in the Acquisition of English as a Third Language. 这是个PDF文档 http://eric.ed.gov/ERICDocs/data/ericdocs2sql/content_storage_01/0000019b/80/19/34/30.pdf Age-Related Factors in Second Language Acquisition (） http://www....
