13 Towards Discontinuous Grammar

ABSTRACT. This paper presents a grammar formalism in which constituent graphs are unions of a continuous surface tree and a discontinuous deep tree. The formalism has an object-oriented design where nodes have their own rules for combining with other nodes. The formalism includes a deterministic parser with a repair operation as a model of human parsing. The formalism is not a complete theory of grammar: It only determines how global word order follows from a lexical theory specifying local properties like dependency relations, landing sites, and local ordering. This theory of the lexicon and its semantics may be adopted from GB, HPSG, LFG, Word Grammar, Pustejovsky’s Generative Lexicon, or almost any other grammar theory. 1 Though languages abound with discontinuous word-order phenomena, most grammar formalisms use continuous syntax trees. This means that discontinuous dependencies must be encoded by some other means than the tree structure. To do so, GB uses movement transformations from deep trees to surface trees, whereas HPSG uses nonlocal features propagated along paths in the tree, and LFG uses path specifications in functional structure. However, with these methods, tough cases of discontinuity are often hard to capture without significant loss of efficiency