tailieunhanh - Constituent Structure - Part 24

Constituent Structure - Part 24 | 110 PHRASE STRUCTURE GRAMMARS AND X-BAR F-equations aren t only licensed by the metavariables they can also act as statements that correspond almost identically to GPSG s meaning postulates. A raising verb like seem has a f-equation in its lexical entry stating that its subject is to be interpreted as the embedded predicate s xcomp in 29 subject. This is similar to the meaning postulates in 23 . 29 seem subj xcomp subj Summary The extensions to constituent structure phrase structure suggested in this section all make reference to mapping the constituent structure onto some kind of enriched semantic structure. The empirical coverage of these extensions although not the practicalities correspond in many cases to the kind of phenomena that transformations and metarules were designed to handle. In the next section we consider extensions that do similar work but instead shift the added empirical burden to the generative lexicon. The lexicon One of the major problems with structure-changing transformations was their unbounded power. In principle you could have a transformational rule turn any sentence into any other sentence. This not only extends the constituent structure but makes it nearly limitlessly powerful Peters and Ritchie 1973 . One way to restrict the power of transformation-like rules is to tie them closely to morphological operations. Under such a view the fact that the argument-reordering principles such as the passive are linked to a particular morphology is explained. If we assume that the lexicon is not a static list but instead is itself a generative engine then we can posit certain kinds of operations that hold only over words and the narrow properties of those words. These are known as lexical rules and are found in LFG HPSG and to a lesser extent in the lexicalist versions of GB and Minimalism. A typical example common to all three approaches would be a lexical-rule approach to passive. The operation that applies passive morphology to the .