Language performance and language acquisition are the two principle concerns of the psych

Language performance and language acquisition are the two principle concerns of the psychology of language, or psycholinguistics.【M1】______ The intensified study of psycholinguistics has produced a considerable amount of literature and some significant advance in our understanding【M2】______ of language acquisition. Surprisingly little fundamental research has been conducted into the processes of learning a second language. The consequence has been most theories in this field【M3】______ are still extrapolating from general theories of human learning【M4】______ and behavior. or from the recent work in language performance and acquisition. This is not to say that there has been no valuable research on language teaching. But this has been concerned about【M5】______ the evaluation of different teaching methods and materials, for example, the use of language laboratories, the use of language drills, the teaching of grammar by different methods. Now, such research is difficult to evaluate, so experiments in【M6】______ language teaching suffer from the same set of problems that all comparative educational experiments suffer from. It is virtually impossible to control all the factors involved in even if we know【M7】______ how to identify them in the first place, particularly such factors as motivation, previous knowledge, aptitude, learning outside the classroom, teacher performance. Consequently the conclusions to be drawn from such experiments can, with confidence, be generalized to other【M8】______ teaching situations. The results are, strictly spoken, only valid for the【M9】______ learners, teachers and schools in what the experiment took place.【M10】______

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