Phrase structure rules - Definition - Encyclopedia II

Phrase structure rules are usually of the form , meaning that the constituent A is separated into the two subconstituents B and C. Some examples are:

The first rule reads: An S consists of an NP followed by a VP. This means A sentence consists of a noun phrase followed by a verb phrase. The next one: A noun phrase consists of a determiner followed by a noun.

Further explanations of the constituents: S, Det, NP, VP, AP

Associated with phrase structure rules is a famous example of a grammatically correct sentence. The sentence was constructed by Noam Chomsky as an illustration that syntactically but not semantically correct sentences are possible.

Colorless green ideas sleep furiously can be diagrammed as a phrase tree, as below:

where S represents a grammatical sentence.

Adapted from the Wikipedia article "Definition", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki/Main_Page