Bilingual Adolescents' Complex Syntax Production in Both Languages Across Conversational and Expository Contexts.

Purpose: Bilingual development has been shown to be highly dependent on language-specific exposure. This study extended the study of bilingual development to adolescence and to the production of complex syntax in two contexts: conversation and expository discourse.

Method: English-French bilinguals (EFbil; = 27) and French L1 speakers ( = 14) aged 12 to 17 years produced French and English conversational and expository samples. Measures of mean length of T-units and clausal density were used, as well as a measure of detailed subordinate clause diversity developed in this study.

Results: Both groups produced more complex syntax in expository discourse compared to conversation and performed very similarly overall. Significant group differences were found in French subordinate clause diversity but not in sentence length or clause density. For EFbil, differences between languages were unexpectedly greater in conversation. Previous language exposure impacted both languages of the EFbil and in both contexts.

Conclusions: This study is the first to report on the spontaneous syntactic use of bilingual adolescents in both their languages. Subtle but significant differences were found in the syntactic skills of the two groups. Expository and conversational contexts each provided unique information on aspects of complex syntactic development, calling into question the idea that the ability to produce a more complex context guarantees conversational abilities. Finally, for the EFbil, previous language exposure impacted both languages, particularly in conversation.

Supplemental Material: https://doi.org/10.23641/asha.23713152.