Realization of Tree Adjoining Grammars with Uni cation

The syntactic generator of the WIP system is based on the representation formalism`Tree Adjoining Grammars' (TAGs). We have extended the formalism by associating elementary rules of the grammar (trees) with feature structures, leading tòTree Adjoining Grammars with Uniication' (UTAGs). The extended formalism facilitates a compact and adequate representation of complex syntactic features. The contradiction between the monotonic operation of uniication and the combination operation for trees { adjunction { that is nonmonotonic in a way can be solved by several diierent approaches to realization. Two of them are presented in this report and compared with respect to the restrictions that are given by the system, i.e., the adequacy of the realization for incremental and parallel generation. It can be shown that UTAGs are subsumed by FTAGs (Feature Structure based TAGs) that have been deened by Vijay-Shanker and Joshi. That is why the results for realization can be applied to both UTAGs and a restricted version of FTAGs.