UC Davis

This dissertation draws on both qualitative and quantitative approaches to investigate the linguistic practices of teachers and children who are learning Mandarin Chinese as a Heritage Language (CHL) in two dual immersion preschools in California. CHL children have been interpreted as novice members in local speech communities who actively explore the linguistic repertoire of their multilingual environment and use their languages or language varieties strategically. This research focuses on Mandarin variation patterns by both teachers and children in school and explores the use of sociolinguistic variables in language input and child production. Specifically, it examines the variation in Mandarin syllable-initial sibilants /s/ and /ʂ/ which are two distinctive phonological categories but are often mixed in several Mandarin varieties.Chapter 2 reviews relevant studies from the perspectives of child language development, bilingual teaching and learning, and sociolinguistics. Chapter 3 introduces the interdisciplinary background of sociolinguistics, then discusses the ethnographic methodology, followed by a detailed explanation of the research methods of the current study. The characteristics of language input and how teachers use sociolinguistic variables in their Mandarin instruction are interpreted in Chapter 4. Chapter 5 examines the bilingual development of CHL children and how this is affected by their age, gender, home language, and enrollment length in the programs. The extent to which children perceive and reproduce the Mandarin sociolinguistic variables in their heritage language is analyzed in Chapter 6. Chapter 7 presents other developmental patterns in Mandarin and English observed in CHL children. Lastly, Chapter 8 summarizes the key findings, highlighting the practical and theoretical implications as well as limitations so as to propose directions for future research. The findings suggest that teachers adjusted their use of variants according to the contexts and that children’s language backgrounds may serve as one of the reasons for their choice of variants. CHL children in the classroom had been exposed to a range of sociolinguistic variables in the school setting. In addition, language use in families plays a key role in explaining the diverse language proficiencies among CHL children. The differences in language proficiency, along with other factors such as age, discourse context, input, and gender significantly affected the ways CHL children chose to use the sibilants in their heritage language. Besides sibilant variation, other developmental and variation patterns have also been identified. From an interdisciplinary perspective, this study contributes to the current knowledge of the acquisition of variation by expanding the research scale into CHL communities where heterogeneous language resources are available for children to explore. It also reveals the potential connection between language input and child language production to illustrate the acquisition process where different variation patterns may compete for salience. In this age group, children start exploring and experimenting with various language features and styles with adults and peers. In addition, this research illustrates the potential of dual immersion to support early childhood development in both CHL and English. By combining children from diverse linguistic backgrounds in the same class, dual immersion programs provide multiple sources of language input and varying contexts to practice the use of different language varieties and styles. They also offer children opportunities to actively establish their own sociolinguistic network with peers with whom they may creatively use their full linguistic repertoire in different languages and varieties.