In the study of natural language understanding, the reductionist approach has been commonly used by A, I. researchers. Here we develop a technique for parsing based on this approach. W e use a set of semantic primitives to represent word meanings and utilize patterns of sentences for mapping sentences onto meaning structures. To assist the parsing process,w e develop semantic mappings for primitive sentences, semantic transformations for decomposing complex sentences using function word sand axioms that encode world knowledge. W e then explore the application of our approach to the word polysemy problem.