First steps toward a usage-based theory of language acquisition*

Usage-based models of language focus on the speci®c communicative events in which people learn and use language. In these models, the psycholinguistic units with which individuals operate are determined not by theoretical ®at but by observation of actual language use in actual communicative events. This data-based approach make these models especially congenial for the analysis of children's language, since children do not learn and use the same units as adults. In this paper I employ a usage-based model of language to argue for ®ve fundamental facts about child language acquisition: (1) the primary psycholinguistic unit of child language acquisition is the utterance, which has as its foundation the expression and understanding of communicative intentions; (2) early in their language development children are attempting to reproduce not adult words but whole adult utterances; (3) children's earliest utterances are almost totally concrete in the sense that they are instantiations of item-based schemas or constructions; (4) abstractions result from children generalizing across the type variation they observe at particular ``slots'' in otherwise recurrent tokens of the same utterance; and (5) children create novel utterances for themselves via usage-based syntactic operations in which they begin with an utterance-level schema and then modify that schema for the exigencies of the particular communicative situation (usage event) at hand.