A study of bilingual development of subject realization of a Mandarin-English bilingual preschool child from China to Australia

This article traces the developmental trajectory of bilingual subject realization of a Mandarin-English bilingual child from China to Australia from age 3;04 to 5;05. There is an assumption that age 3 is the dividing line between Bilingual First Language Acquisition (BFLA) and Early Second Language Acquisition (ESLA). Determining similarities and differences between them is of great theoretical and methodological significance. While BFLA studies show consistent results under the condition of adequate input and meaningful interaction, ESLA studies indicate that these children proceed their early English differently from BFLA. Previous studies mainly focused on young children's English development in English-speaking countries without prior English input. However, an increasing number of children migrate to English-speaking countries after age 1 with limited English input. This study examines whether there is qualitative difference between BFLA and ESLA children's bilingual subject realization. Drawing upon the naturalistic data before and after the child's migration from China to Australia and CLAN analysis, the 25-month longitudinal case study indicates that the ESLA child's bilingual subject realization developmental trajectories are qualitatively similar but quantitatively different from Mandarin-English BFLA peers. This study could be the first of its kind by investigating a bilingual child who acquires two languages with changed environmental language (Lϵ), contributing theoretically and practically to early childhood bilingualism.