The Full Competence Hypothesis of Clause Structure in Early German

We argue that young German children have the major functional sentential heads, in particular the inflectional and complementizer systems. The major empirical basis is natural production data from a 25-month-old child. We perform quantitative analyses which show that the full complement of functional categories is available to the child, and that what crucially distinguishes the child's grammar from the adult's is the use of infinitives in matrix clauses. The evidence we consider includes the child's knowledge of finiteness and verb placement, agreement, head movement, and permissible word-order variations. We examine several accounts which presuppose a degenerate grammar or which deviate from the standard analysis of German and conclude that they provide a less adequate explanation of the acquisition facts.