The Mandarin ba-construction in school-age heritage speakers and their parental input

Recent research has identified language development in school-age heritage children as an important yet missing link between child early bilinguals and adult heritage speakers. This study investigates the Mandarin ba-construction ([(NP1)-ba-NP2-VP]) through elicited narration among heritage Mandarin children (n = 27, aged 4-14) and their parents (n = 18) in the UK. The results showed considerable similarities between the children and their parents in a number of key structural properties of the ba-construction. However, the children produced the ba-construction with reduced frequency and in a "heritage variety" with a reduced set of nominal and verbal phrases in NP2 and VP, which is not attested in a group of age-matched Mandarin speakers in Beijing. Additionally, higher frequency of the ba-construction in the heritage children's production is associated with greater lexical diversity, rather than higher frequency of the ba-construction, in their parental input. We lay out positive aspects of the heritage variety of the ba-construction in sustaining the heritage language in bilingual contexts and consider the different roles of structural frequency and lexical diversity in parental input in maintaining the heritage grammar in late childhood and adolescence.