بررسی تاثیر سطح دانش زبانی زبان آموزان بر میزان و اهداف استفاده از زبان اول توسط معلمدر محیط تدریس انگلیسی به عنوان زبان خارجی

iv abstract this study examined the linguistic behaviors of two iranian efl teachers each of them teaching learners of two similar proficiency levels, a beginner level and an intermediate level, to investigate the relationship between the learners proficiency levels and the amounts and purposes for l1 use by the two teachers. the study was carried out to investigate whether there were differences in the amounts and purposes for l1 use at the two different levels and also to find out whether there were any changes in the teachers l1 use as the learners proficiency increased. data consisted of audio recording one complete lesson of each of the two different levels the two participants taught. first, the word count method was adopted to quantify the amounts and percentages of l1 and tl use, and then the turns were identified and a modified version of the coding scheme developed by rolin-ianzitti and brownlie (2002), which consisted of eight different functions, was used to classify the l1 turns by the teachers on the basis of their functions. quantitative analysis of the data revealed that the teachers were different in the amounts of l1 and tl use at the two different levels, and these amounts did not reveal any consistencies between the two teachers and the two levels. qualitative analysis of the data revealed that one of the teachers used l1 for five different functions and the other one used it for eight different functions. despite some differences in the amounts of l1 use for these purposes by the two teachers, as the results showed, for both teachers with an increase in the learners proficiency levels there was a decrease in the amounts of l1 use for reaction to student request purpose and on the hand, there was an increase in the amounts of l1 use for translation and contrast purposes as the learners levels increased. the results of the study are discussed on the basis of vygotskeys socio-cultural theory. according to this view it was expected to be a decrease in the amounts of l1 use by the two teachers. the results of the study suggest that whereas for one participant it was the case, for the other one the difference between the two levels was negligible, and there was not much difference between the two levels. the v study also showed that l1 can be used as a facilitative and mediating tool in the l2 classroom, and furthermore it showed that regardless of the learners proficiency levels, an amount of l1 use by the teachers seems to be unavoidable. keywords: l1 use, tl use, word count method, socio-cultural theory