Once we are sensitive to the existence of noun phrases, we recognize a relatively simple structure to the sentence. We do not get lost in the flow of words, but recognize structure. At the point that we recognize structure within the sentence, we recognize meaning. Post-modifiers commonly answer the traditional news reporting questions of who , what , where , when , how , or why . In school, we were taught that pronouns replaced nouns .
Pronouns replace complete noun phrases .
Pronoun replacement thus offers a test of a complete noun phrase. The boy ate the apple in the pie. Introduce the pronoun it into the sentence. The boy ate the it in the pie. They d say The boy ate it.