Phrase structure is a widespread approach to the analysis and exploration of sentence structure.
Phrase structure is a widespread approach to the analysis and exploration of sentence structure. Sentences are understood in terms of a part-whole relation, whereby a whole (a sentence) is broken down into its parts, and these parts are broken down into yet smaller parts, etc. until the smallest parts are reached (often just the words). Many of the parts in this process are phrases. Phrase structure stands in contrast to dependency structure. The two, phrase structure and dependency structure, are the main two ways to conceive of how syntactic units are grouped together.