It has seldom been generally acknowledged that whether negative,beneficial or to what extent the role of L1 plays in the process of L2 acquisition,though there’s long been a popular belief that L1 is inevitable and plays an extremely significant role in L2 development.In this article,after relevant literature is historically referred to,the role of L1 that plays in L2 learning process is examined in the cognitive dimension of language,with some secondary researches being discussed.Key words:language;cognitive;
