Survey of the effect of the Semnani language on the mean length of utterance (MLU) of Farsi language among the normal 6-year-old children in the kindergartens affiliated to the education bureau in Semnan

Researchers on advantages and disadvantages of bilingualism have showed the paradoxical results. Some indicate that bilingual language abilities are far behind that of monolinguals. On the other hand, each language affects the mother language and the second one in a different way. Since, Farsi is taught at Iranians schools and on the condition that there are problems in comprehension and/or expression of the concepts in Farsi, so, the pupils are at risk to leave school. There is also a need to do more research on bilingual linguistic competence. The aim of this research was to evaluate the effect of Semnani language on the normal 6-year-old children's MLU as one of the language development indicators. This study has been carried out in 2004 by using the analytical & cross-sectional methods in 14 kindergartens in the south of Semnan city. 576 children were selected randomly. The parents whose children did not have any problems in learning of educational activities, filled in the questionnaire. Those who suffered from hearing deficiency were put aside. Then, 30 bilinguals were selected randomly and 30 monolinguals (Farsi) were matched according to their parent's education and job. These children attended in describing picture test and answered to 2 examiner's questions. Results showing that the difference between MLU in bilinguals and monolinguals is not statistically meaningful. And the mean of MLU; word and morpheme in free and descriptive speech of bilingual males is higher than that of monolinguals. The mean of MLU; word and morpheme in free and descriptive speech of bilingual females is lower than that of monolingual ones. In this research, it could be said that learning Semnani language has not affected on the 6- year- old bilingual children's MLU in Farsi language. On the basis of the above findings in this research, it seems that learning the Semnani language has not had any negative effect on MLU of Farsi language among the 6-year-old children.