Constraints on Parameter Setting: A Grammatical Analysis of Some Acquisition in Stages in German Child Language

In the first part of this article, it is argued that in order to improve the parameter model as a theory of acquisition it has to be constrained in several ways. Three constraints are discussed that restrict the class of possible parameters and the way they are fixed in development. In the second part, empirical results on the acquisition of subject-verb agreement, verb placement, empty subjects, and negation in German child language are presented. I suggest a grammatical analysis for these data (in terms of the Split-Infl Hypothesis) that allows us to maintain the learnability constraints from the beginning.