An ELT Glossary : Noun phrases
A noun phrase is a part of a sentence or utterance that consists of a noun or a pronoun, and any elements (determiners, adjectives etc) that premodify (come before) them or post-modify (come after them). All the underlined expressions in the following sentences are noun phrases :
Leave it alone!
Roses are red...
The books are over there.
The red ones are sweetest
Where's my old, grey coat?
This is a heavily pre-modified noun phrase.
Brown and Yule (1983) pointed out that heavily pre-modified noun phrases - ie nouns with several pre-modifiers piled up in front of them- are rare in spoken English, though very common in written English. In spoken English, information tends to be "chunked" and given one item at a time in order to make real-time processing easier for the listener. See here for their examples.
Noun phrases can also be post-modified, most often by a prepositional phrase (underlined) :
A wide range of items
The man with a beard
or by a relative clause (underlined), often with elements elipted (in brackets):
The person (who is) responsible
Brown G. and Yule G. (1983) Teaching the Spoken Language, Cambridge University Press