ABSTRACT
This chapter argues that although there is developmental change in language knowledge in the area of complex sentence embedding and, in particular, in the development of relative clause structures, children's early hypotheses in this area reflect the presence of adjunction, not its absence. It shows that a wide body of evidence exists that supports the proposal that children do have the grammatical competence for adjunction, a finding that is inconsistent with the conjoin-a-only hypothesis. David Lebeaux proposed that the time course of acquisition can be represented in terms of partial grammars that precede full grammars, where partial grammars were described in terms of individual levels of representation. Speas's theory reflects only partial accord with the Lebeaux proposal, however, because it does not maintain fractionation of levels of representation to define independent adult grammars. The chapter suggests that there is evidence for real developmental change in the child's knowledge of the grammar of certain forms of complex sentence formation.
