Because of this change in the field of second language acquisition, researchers have paid much attention on the learners’ inpidual differences。 They pided these differences into three groups。 The first one contains unchangeable leaner factors such as age, sex and native language。 The second are changeable learner factors such as beliefs, motivations, learning strategies and styles。 The last are various factors such as the target language and the nature of instruction．

In recent years, among these inpidual differences the learning strategies has aroused the most interests of the researchers。 Early researches didn’t classify the strategies into general categories。 They mainly noticed the strategies which learners were observed to use。 With the development of the study, many researchers began to classify the strategies in a systematic way with different points of view。文献综述

Although studies of Language Learning Strategy do not have a long history, learners have come up with a set of strategies consciously or subconsciously to improve their language proficiency。 Researchers wanted to find some relationship between strategies use and language proficiency。 For example，Politzer & McgGroarty (1985) tried to find out the relationship between those which were thought “good learning behaviors” and the scores gained on course。 And the result reveals there were some relationship between the strategy and the proficiency。 Abraham and Vann (1987) found that even using the same strategy, unsuccessful learners can’t do the same good with the successful learners, which were thought as useful。 But in the study of Green & Oxford (1995), students who were better in their language performance usually use the strategy frequently。 And researcher can’t reach an agreement on the relationship between the learning strategie and the language proficiency。