Bilingual acquisition is a fast-growing field of interdisciplinary research, seeking to understand how children acquire two languages simultaneously in the first years of life. Many children grow up in families where more than one language is spoken on a regular basis. This chapter discusses some of the major issues and findings in the study of early bilingual acquisition with special reference to studies involving a Chinese language as one of the target languages.
The field of bilingual acquisition can be characterized as the intersection of child language acquisition and bilingualism (De Houwer, 1998a). Bilingual acquisition, child language acquisition, and bilingualism are fields which mutually inform each other. Bilingual acquisition research investigates how children acquire knowledge of two languages, what this tells us about the nature of language acquisition in general, and how the acquisition of two languages is similar to or different from that of one language only. To address issues in bilingual acquisition, one typically draws on monolingual child language acquisition data to serve as a baseline comparison in order to ascertain the similarities and differences in developmental patterns and rate of development. The methods used in monolingual child language acquisition, longitudinal and cross-sectional, observational and experimental, are also used in bilingual acquisition (see below on methods). In addition, phenomena unique to bilingual acquisition, such as code mixing, can be analyzed using models available in the field of bilingualism (see Bhatia & Ritchie, 2004).