Do young children have adult syntactic competence?

Many developmental psycholinguists assume that young children have adult syntactic competence, this assumption being operationalized in the use of adult-like grammars to describe young children's language. This "continuity assumption" has never had strong empirical support, but recently a number of new findings have emerged - both from systematic analyses of children's spontaneous speech and from controlled experiments - that contradict it directly. In general, the key finding is that most of children's early linguistic competence is item based, and therefore their language development proceeds in a piecemeal fashion with virtually no evidence of any system-wide syntactic categories, schemas, or parameters. For a variety of reasons, these findings are not easily explained in terms of the development of children's skills of linguistic performance, pragmatics, or other "external" factors. The framework of an alternative, usage-based theory of child language acquisition - relying explicitly on new models from Cognitive-Functional Linguistics - is presented.