Hostname: page-component-cb9f654ff-5kfdg Total loading time: 0 Render date: 2025-08-06T07:54:22.225Z Has data issue: false hasContentIssue false
  • English
  • Français

Child, family, and school factors in bilingual preschoolers’ vocabulary development in heritage languages

Published online by Cambridge University Press:  24 February 2020

He SUN ,
Siew Chin NG ,
Beth Ann O'BRIEN  and
Tom FRITZSCHE
He SUN*
Affiliation:
National Institute of Education, Nanyang Technological University, Singapore
Siew Chin NG
Affiliation:
National Institute of Education, Nanyang Technological University, Singapore
Beth Ann O'BRIEN
Affiliation:
National Institute of Education, Nanyang Technological University, Singapore
Tom FRITZSCHE
Affiliation:
Linguistics Department, University of Potsdam, Germany
*
*Corresponding author: Centre for Research in Child Development, National Institute of Education, Nanyang Technological University, NIE5-B3-13, 1 Nanyang Walk, Singapore637616. E-mail: he.sun@nie.edu.sg
Get access Rights & Permissions [Opens in a new window]

Abstract

Child characteristics, family factors, and preschool factors are all found to affect the rate of bilingual children's vocabulary development in heritage language (HL). However, what remains unknown is the relative importance of these three sets of factors in HL vocabulary growth. The current study explored the complex issue with 457 Singaporean preschool children who are speaking either Mandarin, Malay, or Tamil as their HL. A series of internal factors (e.g., non-verbal intelligence) and external factors (e.g., maternal educational level) were used to predict children's HL vocabulary growth over a year at preschool with linear mixed effects models.

The results demonstrated that external factors (i.e., family and preschool factors) are relatively more important than child characteristics in enhancing bilingual children's HL vocabulary growth. Specifically, children's language input quantity (i.e., home language dominance), input quality (e.g., number of books in HL), and HL input quantity at school (i.e., the time between two waves of tests at preschool) predict the participants’ HL vocabulary growth, with initial vocabulary controlled. The relative importance of external factors in bilingual children's HL vocabulary development is attributed to the general bilingual setting in Singapore, where HL is taken as a subject to learn at preschool and children have fairly limited exposure to HL in general. The limited amount of input might not suffice to trigger the full expression of internal resources. Our findings suggest the crucial roles that caregivers and preschools play in early HL education, and the necessity of more parental involvement in early HL learning in particular.

Keywords

heritage language maintenancechild characteristicsinput quantitylanguage input-poor setting

Information

Type
Articles
Information
Journal of Child Language , Volume 47 , Issue 4 , July 2020 , pp. 817 - 843
Copyright
Copyright © Cambridge University Press 2020

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

Article purchase

Temporarily unavailable

References

Aarts, R., & Ronde, S. (2006). Tweetalig onderwijs met vervroegd Engels in het basisonderwijs. Levende Talen Tijdschrift, 7, 3–14.Google Scholar
Akaike, H. (1974). A new look at the statistical model identification. IEEE Transactions on Automatic Control, 19(6), 716–23.CrossRefGoogle Scholar
Armon-Lotem, S., Walters, J., & Gagarina, N. (2011). The impact of internal and external factors on linguistic performance in the home language and in L2 among Russian–Hebrew and Russian–German preschool children. Linguistic Approaches to Bilingualism, 1(3), 291–317.CrossRefGoogle Scholar
August, D., Carlo, M., Dressler, C., & Snow, C. (2005). The critical role of vocabulary development for English language learners. Learning Disabilities Research and Practice, 20, 50–7.CrossRefGoogle Scholar
Baayen, R. H. (2008). Analyzing linguistic data: a practical introduction to statistics using R. Cambridge University Press.CrossRefGoogle Scholar
Barbosa, P. G., Jiang, Z., & Nicoladis, E. (2019). The role of working and short-term memory in predicting receptive vocabulary in monolingual and sequential bilingual children. International Journal of Bilingual Education and Bilingualism, 22(7), 801–17.CrossRefGoogle Scholar
Bates, D., Maechler, M., Bolker, B., & Walker, S. (2015). Fitting linear mixed-effects models using lme4. Journal of Statistical Software, 67(1), 1–48.CrossRefGoogle Scholar
Bedore, L. M., Pena, E. D., Summers, C. L., Boerger, K. M., Resendiz, M. D., Greene, K., Bohman, T. M. & Gillam, R. B. (2012). The measure matters: language dominance profiles across measures in Spanish–English bilingual children. Bilingualism: Language and Cognition, 15(3), 616–29.CrossRefGoogle ScholarPubMed
Blom, E., Paradis, J., & Duncan, T. S. (2012). Effects of input properties, vocabulary size, and L1 on the development of third person singular -s in child L2 English. Language Learning, 62(3), 965–94.CrossRefGoogle Scholar
Bohman, T. M., Bedore, L. M., Pena, E. D., Mendez-Perez, A., & Gillam, R. B. (2010). What you hear and what you say: language performance in Spanish–English bilinguals. International Journal of Bilingual Education and Bilingualism, 13(3), 325–44.CrossRefGoogle ScholarPubMed
Bokhorst-Heng, W. (1999). Singapore's speak Mandarin campaign: language ideological debates in the imagining of the nation. In Blommaert, J. (Ed.). Language ideological debates (pp. 235–65). Berlin: De Gruyter Mouton.Google Scholar
Bornstein, M. H., Haynes, O. M., & Painter, K. M. (1998). Sources of child vocabulary competence: a multivariate model. Journal of Child Language, 25(2), 367–93.CrossRefGoogle ScholarPubMed
Bornstein, M. H., & Leventhal, T. (2015). Children in bioecological landscapes of development. In Lerner, R. M. (Ed.), Handbook of child psychology and developmental science (pp. 1–5). Hoboken, NJ: John Wiley & Sons.Google Scholar
Burgess, S. R., Hecht, S. A., & Lonigan, C. J. (2002). Relations of home literacy environment (HLE) to the development of reading-related abilities: a one-year study. Reading Research Quarterly, 37, 408–26.CrossRefGoogle Scholar
Bus, A. G., van IJzendoorn, M. H., & Pellegrini, A. D. (1995). Joint book reading makes for success in learning to read: a meta-analysis on intergenerational transmission of literacy. Review of Educational Research, 65, 1–21.CrossRefGoogle Scholar
Cohen, D. K., Raudenbush, S. W., & Ball, D. L. (2003). Resources, instruction, and research. Educational Evaluation and Policy Analysis, 25(2), 119–42.CrossRefGoogle Scholar
Collins, B. A. (2014). Dual language development of Latino children: effect of instructional program type and the home and school language environment. Early Childhood Research Quarterly, 29, 389–97.CrossRefGoogle ScholarPubMed
Connor, C. M., Morrison, F. J., & Slominski, L. (2006). Preschool instruction and children's emergent literacy growth. Journal of Educational Psychology, 98(4), 665–89.CrossRefGoogle Scholar
Connor, C. M., Son, S. H., Hindman, A. H., & Morrison, F. (2005). Teacher qualifications, classroom practices, family characteristics, and preschool experience: complex effects on first graders’ vocabulary and early reading outcomes. Journal of School Psychology, 43(4), 343–75.CrossRefGoogle Scholar
Cummins, J. (2001). Bilingual children's mother tongue: Why is it important for education? Sprogforum, 19, 15–20.Google Scholar
Cummins, J. (2005). A proposal for action: strategies for recognizing heritage language competence as a learning resource within the mainstream classroom. Modern Language Journal, 89(4), 585–92.Google Scholar
Curdt-Christiansen, X. L. (2016). Conflicting language ideologies and contradictory language practices in Singaporean multilingual families. Journal of Multilingual and Multicultural Development, 37(7), 694–709.CrossRefGoogle Scholar
Dąbrowska, E. (2012). Different speakers, different grammars: individual differences in native language attainment. Linguistic Approaches to Bilingualism, 2(3), 219–53.CrossRefGoogle Scholar
Dąbrowska, E. (2016). Cognitive Linguistics’ seven deadly sins. Cognitive Linguistics, 27(4), 479–91.CrossRefGoogle Scholar
Daller, M., & Ongun, Z. (2018). The threshold hypothesis revisited: bilingual lexical knowledge and nonverbal IQ development. International Journal of Bilingualism, 22(6), 675–94.CrossRefGoogle Scholar
De Houwer, A. (2007). Parental language input patterns and children's bilingual use. Applied Psycholinguistics, 28(3), 411–24.CrossRefGoogle Scholar
De Houwer, A. (2018). The role of language input environments for language outcomes and language acquisition in young bilingual children. In Miller, D., Bayram, F., Rothman, J., & Serratrice, L. (Eds.), Bilingual cognition and language: the state of the science across its subfields (pp. 127–54). Amsterdam: John Benjamins.CrossRefGoogle Scholar
De Jong, P. F., Seveke, M. J., & van Veen, M. (2000). Phonological sensitivity and the acquisition of new words in children. Journal of Experimental Child Psychology, 76, 275–301.CrossRefGoogle ScholarPubMed
Dickinson, D. K. (2011). Teachers’ language practices and academic outcomes of preschool children. Science, 333, 964–67.CrossRefGoogle ScholarPubMed
Dickinson, D. K., & Porche, M. V. (2011). Relation between language experiences in preschool classrooms and children's kindergarten and fourth-grade language and reading abilities. Child Development, 82(3), 870–86.CrossRefGoogle ScholarPubMed
Dijkstra, J., Kuiken, F., Jorna, R. J., & Klinkenberg, E. L. (2016). The role of majority and minority language input in the early development of a bilingual vocabulary. Bilingualism, 19(1), 191–205.CrossRefGoogle Scholar
Dixon, L. Q., Zhao, J., Quiroz, B. G., & Shin, J. Y. (2012). Home and community factors influencing bilingual children's MTL vocabulary development. International Journal of Bilingualism, 16(4), 541–65.CrossRefGoogle Scholar
Druten-Frietman, L. V., Denessen, E., Gijsel, M., & Verhoeven, L. (2015). Child, home and institutional predictors of preschool vocabulary growth. Learning and Individual Differences, 43, 92–9.CrossRefGoogle Scholar
Duursma, E., Romero-Contreras, S., Szuber, A., Proctor, P., Snow, C., August, D., & Calderon, M. (2007). The role of home literacy and language environment on bilinguals’ English and Spanish vocabulary development. Applied Psycholinguistics, 28, 171–90.CrossRefGoogle Scholar
Ebert, S., Lockl, K., Weinert, S., Anders, Y., Kluczniok, K, & Rossbach, H. G. (2013). Internal and external influences on vocabulary development in preschool children. School Effectiveness and School Improvement: An International Journal of Research, Policy and Practice, 24(2), 138–54.CrossRefGoogle Scholar
Eriksson, M., Marschik, P. B., Tulviste, T., Almgren, M., Perez Pereira, M., Wehberg, S., et al. (2012). Differences between girls and boys in emerging language skills: evidence from 10 language communities. British Journal of Developmental Psychology, 30(2), 326–43.CrossRefGoogle Scholar
Farver, J. A. M., Xu, Y., Eppe, S., & Lonigan, C. J. (2006). Home environments and young Latino children's school readiness. Early Childhood Research Quarterly, 21(2), 196–212.CrossRefGoogle Scholar
Field, A. (2009). Discovering statistics using SPSS. London: SAGE.Google Scholar
Floccia, C., Sambrook, T. D., Delle Luche, C., Kwok, R., Goslin, J., White, L., & Plunkett, K. (2018). Vocabulary of 2-year-olds learning English and an additional language: norms and effects of linguistic distance. Monographs of the Society for Research in Child Development, 83(1), 7–108.CrossRefGoogle Scholar
Ganuza, N., & Hedman, C. (2017). The impact of mother tongue instruction on the development of biliteracy: evidence from Somali–Swedish bilinguals. Applied Linguistics, 40(1), 108–31.CrossRefGoogle Scholar
Gathercole, S. E., & Baddeley, A. D. (1989). Evaluation of the role of phonological STM in the development of vocabulary in children: a longitudinal study. Journal of Memory and Language, 28(2), 200–13.CrossRefGoogle Scholar
Gathercole, S. E., Alloway, T. P., Willis, C., & Adams, A.-M. (2006). Working memory in children with reading disabilities. Journal of Experimental Child Psychology, 93(3), 265–81.CrossRefGoogle ScholarPubMed
Gathercole, V. M. (2018). Language development in bilingual children: fact, factoid and fiction. In Siiner, M., Hult, F. M., & Kupisch, T. (Eds.), Language policy and language acquisition planning (pp. 237–55). New York: Springer.CrossRefGoogle Scholar
Gerde, H. K., & Powell, D. R. (2009). Teacher education, book-reading practices, and children's language growth across one year of Head Start. Early Education and Development, 20, 211–37.CrossRefGoogle Scholar
Gravetter, F., & Wallnau, L. (2014). Essentials of statistics for the behavioral sciences (8th ed.). Belmont, CA: Wadsworth.Google Scholar
Gutiérrez-Clellen, V. F., & Kreiter, J. (2003). Understanding child bilingual acquisition using parent and teacher reports. Applied Psycholinguistics, 24(2), 267–88.CrossRefGoogle Scholar
Hamilton, A., Plunkett, K., & Schafer, G. (2000). Infant vocabulary development assessed with a British communicative development inventory. Journal of Child Language, 27(3), 689–705.CrossRefGoogle ScholarPubMed
Hammer, C. S., Davison, M. D., Lawrence, F. R., & Miccio, A. W. (2009). The effect of maternal language on bilingual children's vocabulary and emergent literacy development during Head Start and kindergarten. Scientific Studies of Reading, 13, 99–121.CrossRefGoogle ScholarPubMed
Hammer, C. S., Farkas, G., & Maczuga, S. (2010). The language and literacy development of Head Start children. a study using the family and child experiences survey database. Language, Speech, and Hearing Services in Schools, 41(1), 70–83.Google ScholarPubMed
Hammer, C. S., Komaroff, E., Rodriguez, B. L., Lopez, L. M., Scarpino, S. E., & Goldstein, B. (2012). Predicting Spanish–English bilingual children's language abilities. Journal of Speech, Language, & Hearing Research, 55(5), 1251–64.CrossRefGoogle ScholarPubMed
Hayes, D. P., & Ahrens, M. G. (1988). Vocabulary simplification for children: a special case of ‘motherese’? Journal of Child Language, 15(2), 395–410.CrossRefGoogle Scholar
Hoff, E., & Elledge, C. (2005). Bilingualism as one of many environmental variables that affect language development. In Cohen, J., McAlister, K. T., Rolstad, K., & MacSwan, J. (Eds.), Proceedings of the 4th International Symposium on Bilingualism (pp. 1034–40). Somerville, MA: Cascadilla Press.Google Scholar
Hornberger, N. H., & Vaish, V. (2008). Multilingual language policy and school linguistic practice: globalization and English-language teaching in India, Singapore, and South Africa. Journal of Comparative Education, 39, 305–20.Google Scholar
Huttenlocher, J., Vasilyeva, M., Cymerman, E., & Levine, S. (2002). Language input and child syntax. Cognitive Psychology, 45(3), 337–74.CrossRefGoogle ScholarPubMed
Jaeger, T. F. (2008). Categorical data analysis: away from ANOVAs (transformation or not) and towards logit mixed models. Journal of Memory and Language, 59(4), 434–46.CrossRefGoogle ScholarPubMed
Jia, G., & Fuse, A. (2007). Acquisition of English grammatical morphology by native Mandarin-speaking children and adolescents: age-related differences. Journal of Speech, Language, and Hearing Research, 50, 1280–99.CrossRefGoogle ScholarPubMed
Lee, L. C., Sze, W. P., & Rickard-Liow, S. J. (2013). Bilingual Language Assessment Battery. National University of Singapore.Google Scholar
Lewis, K., Sandilos, L. E., Hammer, C. S., Sawyer, B. E., & Méndez, L. I. (2016). Relations among the home language and literacy environment and children's language abilities: a study of Head Start dual language learners and their mothers. Early Education and Development, 27(4), 478–94.CrossRefGoogle ScholarPubMed
Marchman, V. A., Fernald, A., & Hurtado, N. (2010). How vocabulary size in two languages relates to efficiency in spoken word recognition by young Spanish–English bilinguals. Journal of Child Language, 37(4), 817–40.CrossRefGoogle Scholar
Mashburn, A. J., Pianta, R. C., Hamre, B. K., Downer, J. T., Barbarin, O., Bryant, D. et al. (2008). Measures of classroom quality in prekindergarten and children's development of academic, language, and social skills. Child Development, 79, 732–49.CrossRefGoogle ScholarPubMed
Miccio, A. W., Tabors, P. O., Páez, M. M., Hammer, C. S., & Wagstaff, D. A. (2005). Vocabulary development in Spanish-speaking Head Start children of Puerto Rican descent. In Cohen, J., McAlister, K. T., Rolstad, K., & MacSwan, J. (Eds.), ISB4: Proceedings of the 4th International Symposium on Bilingualism (pp. 1614–17). Somerville, MA: Cascadilla Press.Google Scholar
Ministry of Education (2013). Framework for mother tongue languages. Retrieved from <https://www.nel.sg/qql/slot/u143/Resources/Downloadable/pdf/nel-framework/nel-framework-for-mtls.pdf>..>Google Scholar
Mol, S. E., & Bus, A. G. (2011). To read or not to read: a meta-analysis of print exposure from infancy to early adulthood. Psychological Bulletin, 137(2), 267–96.CrossRefGoogle ScholarPubMed
Montag, J. L., Jones, M. N., & Smith, L. B. (2015). The words children hear: picture books and the statistics for language learning. Psychological Science, 26(9), 1489–96.CrossRefGoogle ScholarPubMed
Montrul, S. (2002). Incomplete acquisition and attrition of Spanish tense/aspect distinctions in adult bilinguals. Bilingualism: Language and Cognition, 5, 39–68.CrossRefGoogle Scholar
Montrul, S. (2010). Current issues in heritage language acquisition. Annual Review of Applied Linguistics, 30, 3–23.CrossRefGoogle Scholar
Montrul, S. (2018). Heritage language development: connecting the dots. International Journal of Bilingualism, 22(5), 530–46.CrossRefGoogle Scholar
Muñoz, C. (2006). The effects of age on foreign language learning: The BAF Project. In Munoz, C. (Ed.), Age and the rate of foreign language learning (pp. 1–40). Clevedon: Multilingual Matters.CrossRefGoogle Scholar
Muñoz, C. (2008). Symmetries and asymmetries of age effects in naturalistic and instructed L2 learning. Applied Linguistics, 29(4), 578–96.CrossRefGoogle Scholar
NICHD ECCRN (National Institute of Child Health and Human Development Early Child Care Research Network) (2002). Early child care and children's development prior to school entry: results from the NICHD study of early child care. American Education Research Journal, 39, 133–64.CrossRefGoogle Scholar
Ortega, L. (2019). The study of heritage language development from a bilingualism and social justice perspective. Language Learning. doi:10.1111/lang.12347Google Scholar
Paradis, J. (2011). Individual differences in child English second language acquisition: comparing child-internal and child-external factors. Linguistic Approaches to Bilingualism, 1, 213–37.CrossRefGoogle Scholar
Pearson, B. Z., Fernández, S. C., Lewedeg, V., & Oller, K. (1997). The relation of input factors to lexical learning by bilingual infants. Applied Psycholinguistics, 18(1), 41–58.CrossRefGoogle Scholar
Pham, G., & Tipton, T. (2018). Internal and external factors that support children's minority first language and English. Language, Speech, & Hearing Services in Schools, 49(3), 595–606.CrossRefGoogle ScholarPubMed
Phillips, B. M., & Lonigan, C. L. (2009). Variations in the home literacy environment of preschool children: a cluster analytic approach. Scientific Studies of Reading, 13(2), 146–74.CrossRefGoogle ScholarPubMed
Pickering, S., & Gathercole, S. E. (2001). Working Memory Test Battery for Children (WMTB-C). London: Psychological Corporation.Google Scholar
Place, S., & Hoff, E. (2011). Properties of dual language exposure that influence 2-year-olds’ bilingual proficiency. Child Development, 82(6), 1834–49.CrossRefGoogle ScholarPubMed
Polinsky, M. (1995). Cross-linguistic parallels in language loss. Southwest Journal of Linguistics, 14, 87–123.Google Scholar
Portes, A., & Rumbaut, R. (2001). Legacies: the story of immigrant second generation. Berkeley, CA: University of California Press.Google Scholar
Portes, A., & Schauffler, R. (1994). Language and the second generation: bilingualism yesterday and today. International Migration Review, 28(4), 640–61.CrossRefGoogle Scholar
Proctor, C. P., Uccelli, P., Dalton, B., & Snow, C. E. (2009). Understanding depth of vocabulary online with bilingual and monolingual children. Reading and Writing Quarterly, 25(4), 311–33.CrossRefGoogle Scholar
R Core Team (2017). R: a language and environment for statistical computing. Retrieved from <https://www.R-project.org/>..>Google Scholar
Raven, J., Raven, J. C., & Court, J. H. (2008). Manual for Raven's Progressive Matrices and Vocabulary Scales. Section 3: The Standard Progressive Matrices. San Antonio, TX: Harcourt Assessment.Google Scholar
Rickard-Liow, S. J., Sze, W. P., & Lee, L. C. (2013). Bilingual Language Assessment Battery (BLAB) Manual (Unpublished measure). Singapore: National University of Singapore, Department of Psychology and Division of Graduate Medical Studies.Google Scholar
Roberts, J., Jergens, J., & Burchinal, M. (2005). The role of home literacy practices in preschool children's language and emergent literacy skills. Journal of Speech, Language, and Hearing Research, 48, 345–59.CrossRefGoogle ScholarPubMed
Rojas, R., Iglesias, A., Bunta, F., Goldstein, B., Goldenberg, C., & Reese, L. (2016). Interlocutor differential effects on the expressive language skills of Spanish-speaking English learners. International Journal of Speech-Language Pathology, 18(2), 166–77.CrossRefGoogle ScholarPubMed
Saravanan, V. (2001). The significance of bilingual Chinese, Malay and Tamil children's English network patterns on community language use patterns. Early Child Development and Care, 166, 81–91.CrossRefGoogle Scholar
Scheele, A. F., Leseman, P. P., & Mayo, A. Y. (2010). The home language environment of monolingual and bilingual children and their language proficiency. Applied Psycholinguistics, 31(1), 117–40.CrossRefGoogle Scholar
Sénéchal, M., LeFevre, J. A., Thomas, E. M., & Daley, K. E. (1998). Differential effects of home literacy experiences on the development of oral and written language. Reading Research Quarterly, 33, 96–116.CrossRefGoogle Scholar
Snow, C. (1983). Literacy and language: relationships during the preschool years. Harvard Educational Review, 53(2), 165–89.CrossRefGoogle Scholar
Soper, D. S. (2019). Post-hoc statistical power calculator for hierarchical multiple regression [software]. Retrieved from <http://www.danielsoper.com/statcalc>..>Google Scholar
Sun, H., de Bot, K., & Steinkrauss, R. (2015). A multiple case study on the effects of temperamental traits in Chinese preschoolers learning English. International Journal of Bilingualism, 19(6), 703–25.CrossRefGoogle Scholar
Sun, H., Steinkrauss, R., Tendeiro, J., & de Bot, K. (2016). Individual differences in very young children’s English acquisition in China: Internal and external factors. Bilingualism: Language and Cognition, 19(3), 550–566. https://doi.org/10.1017/S1366728915000243.CrossRefGoogle Scholar
Sun, H., Steinkrauss, R., Wieling, M., & de Bot, K. (2018). Individual differences in very young Chinese children's English vocabulary breadth and semantic depth: Internal and external factors. International Journal of Bilingual Education and Bilingualism, 21(4), 405–425. https://doi:10.1080/13670050.2016.1178706CrossRefGoogle Scholar
Sun, H., Toh, W. M., & Steinkrauss, R. (in press). Instructional strategies and linguistic features of kindergarten teachers’ shared book reading: the case of Singapore. Applied Psycholinguistics.Google Scholar
Sun, H., Yin, B., Amsah, F., & O'Brien, B. A. (2018). Differential effects of internal and external factors in early bilingual vocabulary learning: the case of Singapore. Applied Psycholinguistics, 39(2), 383–411.CrossRefGoogle Scholar
Sun, H., Yussof, N., Vijayakumar, P., Lai, G., O'Brien, B. A., & Ong, Q. H. (2019). Teacher's code-switching and bilingual children's heritage language learning and cognitive switching flexibility. Journal of Child Language. https://doi.org/10.1017/S030500091900059XGoogle ScholarPubMed
Swain, M. (2007). The Output Hypothesis: its history and its future. Beijing Foreign Studies University.Google Scholar
Tomasello, M. (2003). Constructing a language: a usage-based theory of language acquisition. Cambridge, MA: Harvard University Press.Google Scholar
Thordardottir, E. (2011). The relationship between bilingual exposure and vocabulary development. International Journal of Bilingualism, 15, 426–45.CrossRefGoogle Scholar
Unsworth, S. (2013). Assessing the role of current and cumulative exposure in simultaneous bilingual acquisition: the case of Dutch gender. Bilingualism: Language and Cognition, 16, 86–110.CrossRefGoogle Scholar
Unsworth, S., Hulk, A., & Marinis, T. (2011). Internal and external factors in child second language acquisition. Linguistic Approaches to Bilingualism, 1, 207–12.CrossRefGoogle Scholar
Unsworth, S., Persson, L., Prins, T., & de Bot., K. (2015). An investigation of factors affecting early foreign language learning in the Netherlands. Applied Linguistics, 35(5), 527–48.Google Scholar
Wells, G. (1986). Variation in child language. In Fletcher, P. & Garman, M. (Eds.), Language acquisition: studies in first language development (pp. 109–39). Cambridge University Press.CrossRefGoogle Scholar
Zhang, D., & Koda, K. (2011). Home literacy environment and word knowledge development: a study of young learners of Chinese as a heritage language. Bilingual Research Journal, 34, 4–18.CrossRefGoogle Scholar
Zhang, X., Hu, B. Y., Ren, L., Huo, S., & Wang, M. (2019). Young Chinese children's academic skill development: identifying child-, family-, and school-level factors. In Liu, Y. (Ed.), Child and Adolescent Development in China. Special issue of New Directions for Child and Adolescent Development, 2019(163), 9–37.Google ScholarPubMed