【Abstract】The study of Second language acquisition varies greatly but one concern is the variables of language learning. The paper illustrates three individual variables in second language acquisition: language aptitude, attitude and learning strategies.
　　【Key words】Individual variables; Second language acquisition
　　1. Introduction
　　During the past few decades, the possible relation between first and second language acquisition has long captured the imagination of second language researchers. The study of language acquisition has always included an interest in finding the relation between the neurological structures and the behavioral indices for language learning. Second language acquisition is now the preferred term for referring to the field within the applied linguistics of language teaching. The paper illustrates three individual variables in second language acquisition: language aptitude, attitude and learning strategies.
　　2. Individual variables
　　Some research concerned SLA as a way of testing hypotheses about the nature of language learning. According to some hypotheses research, Individual variables affect greatly on the language acquisition of the learners. There are three individual variables to be covered in this paper.
　　2.1 Language aptitude
　　Regardless of the age of the learner, what is undeniable is that individuals learn languages at different rates. What is contested, however, is just why this is the case. It is considered that some of the differences can be attributed to specific language aptitude. Aptitude corresponds to the notion when approaching a particular learning task, and the individual’s capability of dealing the task differs. That capability depends on some combination of characteristics of the individual. The term suggests that aptitude is multidimensional. Foreign language aptitude consisted of four independent abilities.(Carroll) Learner’s language aptitude differs greatly from person to person.
　　2.2 Attitude
　　Based on correlations, attitudes were said to have an important and indirect effect on SLA. Of all the possible attitudes that could have this indirect relationship with SLA, the one most extensively researched has been the learners’ attitude towards the target language. Most of the studies demonstrated that a positive attitude towards the target language was related to SLA success. Most of the research in the area of attitudes and SLA deals with the language learners’ views of the target language group. It is found that good language learners normally take active attitude towards language learning. Learner’s attitude plays an important part of successful language acquisition. 　　2.3 Learning strategies
　　Language aptitude, attitude and personality constitute main factors that affect the rate and level of second language achievement. But how does their influence operate? One possibility is that they affect the nature and the frequency with which individual learner uses learning strategies and meaning. Good language learners are also very active because they use strategies for taking charge of their own personal learning, showing awareness of the learning process and their own personal learning styles .And they are flexible and appropriate in their use of learning strategies. They seem to be especially proficient at using cognitive strategies. The study of learning strategies is of potential value to language teachers. If those strategies that are crucial for learning can be more accurately identified, it may be possible to train students to use them. The study of learning strategies is of great value to language teaching.
　　3. Conclusion
　　SLA is still a relatively new discipline and, no wonder; it has captured the imagination of quite a number of researchers in relevant fields. Some have been primarily concerned with language pedagogy and have seen SLA as a contribution to more effective language teaching. Others have been more concerned with linguistics and have seen SLA as a way of testing hypotheses about the nature of language. Still, others have been concerned with multilingual communities and are interested in SLA because it serves to illustrate how social context affects and is affected by language. The research of individual variables in Second Language Acquisition will contribute to the efficiency Language learning.
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