Review of Research on Language Transfer and Two Language,Three Language Acquisition

Since the 1960s,the theory of language transfer theory,language acquisition,especially the two language acquisition theory has been an important subject in the field of applied linguistics. In the world of cultural diversity,historical context of economic integration,with the help of two language acquisition research,three language acquisition research has become a new focus of applied linguistics. On three language acquisition in the words,two language also involved under the influence of social and psychological factors is more complex,fast learner's language ability.