8Corder, S.P. Error analysis, interlanguage and sec- ond language acquisition. Language Teaching & Linguistics: Surveys [ M]. Cambridge University Press, 1978:60 -78.
9Selinker, L. Language Transfer [J]. General Lin- guistics, 1969, 9 : 67 - 92.
10Sandura, A. Social learning theory [ M ]. Engle- wood Cliffs, NJ: Prentice Hall, 1977.
