Extracting the Unextractable: A Case Study on Verb-particles

This paper proposes a series of techniques for extracting English verb–particle constructions from raw text corpora. We initially propose three basic methods, based on tagger output, chunker output and a chunk grammar, respectively, with the chunk grammar method optionally combining with an attachment resolution module to determine the syntactic structure of verb–preposition pairs in ambiguous constructs. We then combine the three methods together into a single classifier, and add in a number of extra lexical and frequentistic features, producing a final F-score of 0.865 over the WSJ.