German Noun Plurals in Simultaneous Bilingual vs. Successive Bilingual vs. Monolingual Kindergarten Children: The Role of Linguistic and Extralinguistic Variables

(1) Background: The complex phenomenon of German noun plural inflection is investigated in three groups of German-speaking kindergarten children: (a) monolinguals (1L1), (b) simultaneous bilinguals (2L1) also acquiring Croatian, and (c) successive bilinguals (L2) acquiring Turkish as L1. Predictions of the usage-based schema model and of Natural Morphology concerning different linguistic variables are used to explore their impact on plural acquisition in the three groups of children. (2) Methods: A longitudinal study (from mean age 3;1 to 4;8) is conducted using two procedures (a formal plural test and spontaneous recordings in kindergarten), and the data are analyzed using generalized linear (mixed-effects) regression models in R. (3) Results: All children produce more errors in the metalinguistically challenging test compared to spontaneous speech, with L2 children being particularly disadvantaged. Socioeconomic status (henceforth SES) and teachers’ plural type frequency are most relevant for 1L1 children, and kindergarten exposure is more relevant for L2 children, while the linguistic variables are more important for 2L1 children. (4) Conclusions: The main predictions of the schema model and of Natural Morphology are largely confirmed. All of the linguistic variables investigated show significant effects in some analyses, but morphotactic transparency turns out to be the most relevant variable for all three groups of children.