Morphosyntactic dependencies

Abstract This chapter introduces the question of how children acquire morphosyntactic dependencies—relationships between two syntactic elements—and focuses on the head-complement dependency between auxiliary verbs and their VP complements (is-V-ing, not can-V-ing) as a case study. Experiments demonstrating knowledge of this nonadjacent dependency by 18 months are subject to careful examination, with potential alternative hypotheses about children’s performance considered (e.g., the idea that they don’t track syntactic dependencies but merely predict that certain elements should occur in a string based on other elements having occurred). The chapter then raises the question of how children acquire knowledge of the is-V-ing dependency and, more generally, how babies learn that any two elements are related when intervening material is present. In this context, experiments on statistical learning are discussed. The chapter concludes by contrasting input-driven and knowledge-driven theories of mapping between strings and underlying syntactic structures.