Lexical acquisition and semantic representation of English phrasal verbs in ontological semantics

The purpose of the present study was to describe and analyze the lexical acquisition and semantic representation of English Phrasal Verbs in Ontological Semantics, a theory of meaning developed by Raskin and Nirenburg and implemented in the Knowledge Base Acquisition Editor, a Natural Language Processing database. Lexical acquisition of phrasal verbs is problematic for two reasons: the discontinuous structure and heterogeneity of meaning structure of phrasal verbs. Although the non-compositionality of meaning is often posed as the main identifying criterion, purely non-compositional phrasal verbs constitute but a part of a much larger class which is frequently marked by varying degrees of metaphoricity. The present study is an account for both structural and semantic diversity of phrasal verbs. In the present study, phrasal verbs were classified into subgroups according to their meaning and then distributed among four basic templates with respect to their composition and permissible orders within the phrasal group. The study suggests a methodology for covering a wide variety of meanings and argues for listing not only non-compositional, but also literal metaphorically extended senses. The main problems encountered during the acquisition were dealing with complex events and sense reduction. These are discussed in case studies as well as in the section on the range of meanings conveyed by individual particles. The results of the acquisition are considered in the light of the sense disambiguation problem in computational semantics and are concluded by a suggestion for a possible revision of the approach to the grammatical category of verbs in general linguistics.