by Roeper and de Villiers contains new experimental evidence concerning
the development of knowledge of constraints on wh-movement. The
chapter by Goodluck and Behne contains new experimental evidence on the
development of control (PRO) constructions, including previously untested
constructions (purpose clauses). The chapter by Weissenborn presents new
data on subjectless sentences (pro-drop) from the acquisition of French and
German. The chapter by Hyams uses recent linguistic theory to develop new
analyses of existing data on the same topic. The chapters are accompanied
by commentary chapters written by scholars from a range of disciplines:
linguistics, psychology, and computer science.

This volume grows out of a roundtable session at the XIVth International
Congress of Linguists, East Berlin, 12 and 14 August, 1987. Most of the
papers were presented there in preliminary form; an exception is the chapter
by Hyams, which was presented at the 12th Annual Boston University
Conference on Language Development, October 1987.

We thank Ken Wexler, who presented a paper at the Berlin workshop,
and all the participants in the workshop, for their comments.

Jürgen Weissenborn
Helen Goodluck
Thomas Roeper

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