Competence and processing in children's grammar of relative clauses

We report two toy-manipulation experiments investigating 4–5-year-old children's interpretations of relative clauses. In the first experiment we show that the frequency with which relatives modifying the matrix direct object are interpreted as referring to the matrix subject is sensitive to the nature of the material in the relative. Animacy of the relative direct object leads to an increase in subject coreference errors for relatives; a similar effect of animacy was not found for infinitival complements. We propose that such errors arise when the child's sentence processor is taxed. In our second experiment we compare children's interpretations of relatives to their interpretations of temporal participial complements. Children eschewed coreference between the complement and the object of a passive prepositional phrase in the case of temporal participials but not in the case of relatives. We interpret this result as evidence that children are capable of analyzing relatives as constituents of the NP node, and hence that this node is recursive in their grammars. We discuss the results of both experiments in the context of a two-stage parsing model, arguing that our data fit a picture of children's linguistic abilities in which the 4-year-old has a sophisticated competence grammar and a parsing mechanism of essentially the same structure as the adult's. We compare our approach to a number of other approaches to children's relative clause interpretations in the literature, arguing that these alternatives are too structure-specific and can lead to underestimations of the child's competence grammar. We conclude that our analysis is compatible with a picture of acquisition in which the child's competence grammar of relatives is not qualitatively different from the adult's.