Null objects in Polish heritage language acquisition in contact with German

This study investigates the acquisition of referential expressions for direct objects by child heritage speakers of Polish living in Germany. Our main research questions are how object expression develops in bilingual children and whether their path or pace of acquisition differs from monolingual children. We investigate the use of referential expressions in an elicited production task. In all, 39 Polish-German bilingual children participated in the test. We compare the data of four age groups of bilingual children – 3- to 4-year-olds, 5- to 6-year-olds, 7- to 8-year-olds, and 9- to 10-year-olds – to each other and to monolingual children at the respective ages. For the analysis of participants’ responses, we ran a generalized linear mixed model (GLMM) with a multinominal dependent variable. The results show that child heritage language (HL) speakers of Polish display knowledge of semantic and pragmatic constraints of object realization from early stages on. However, from age 5 and up to age 9 to 10, they still produce high rates of inappropriate null objects and show a deceleration in the development of this knowledge, compared to monolingual children. This protracted development is attributed to reduced input in the HL, mainly due to the enrolment in the majority language school. This study is the first to investigate the development of referential expressions for direct objects in child heritage speakers of Polish in the age span 3 to 10 years. The study relates the higher rates of null objects in the bilingual production to the varying degrees of exposure to the HL during language development. Deceleration in the pace of object acquisition by the HL speakers at the age of 5 to 6 years is attributed to a prolonged stage of acquisition of integrating rules of syntactic and pragmatic knowledge.