This review article presents evidence for the claim that frequency effects are pervasive in children's first language acquisition, and hence constitute a phenomenon that any successful account must explain. The article is organized around four key domains of research: children's acquisition of single words, inflectional morphology, simple…

Presents a study of young children's understanding that pronouns and proper names cannot be modified by pronominal adjectives. Some nonsyntactic theories are discussed that support the claim that children understand knowledge of word order through the rules that order abstract linguistic categories. (31 references) (GLR)

Reviews the properties and consequences of the Principle of Contrast. It is argued that this principle accounts for the acquisition of irregular forms in morphology and that it plays a crucial role in the acquisition of allomorphy. (62 references) (GLR)

Provides an experimental validation of Landau and Gleitman's (1985) syntactic bootstrapping procedure on how children may use syntactic information to learn new verbs. The children's choice of the correct referent for a given verb versus a nonsense verb in two syntactic structures is explained. (37 references) (GLR)

Two experiments indicating that children's linguistic generalizational biases change from a semantically-based system to a syntactical-structural system provide evidence for a semantic-relational bias in children's early grammars and support the notion that children's generalizational biases shift from a semantic-relational basis to a…