NTUMT Strategy for Prepositional-Phrase Attachment

This paper aims to propose a new parsing strategy to tackle the notorious prepositional-phrase attachment problem (PP attachment problem) in our NWMT system. First of all, correct PP attachment is determined in our PP-Attachment Table (PAT), which requires both syntactic and semantic analyses of verbs, nouns and prepositions in lexicon. PAT is indeed the component where all the idiosyncratic attachment conditions are specified for prepositions. As to our parsing strategy, it can be considered as an interaction between two drivers -- Intelligent ATN (IATN) and Phrase Structure ATN (PATN). IATN scans the input sentence leftwards and activates PA TN to construct the first bar-level structures. PA TN is then responsible for building up structures whenever IA TN gives the command. Correct PP attachment is governed by the seven states in the IA TN Grammar, giving priority to verbs. Since our system just outputs one parsing tree, for a PP which is ambiguous in attaching both to the preceding verb and the preceding noun, the PP will be assigned to be verb modifier.