We introduce the concept of hybrid grammars, which are extensions of synchronous grammars, obtained by coupling of lexical elements. One part of a hybrid grammar generates linear structures, another generates hierarchical structures, and together they generate discontinuous structures. This formalizes and generalizes some existing mechanisms for dealing with discontinuous phrase structures and non-projective dependency structures. Moreover, it allows us to separate the degree of discontinuity from the time complexity of parsing.
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