A noun phrase is a group of two or more words standing together as a single unit, functioning as a noun in a sentence, having a noun and other modifiers, and lacking both a subject and a verb.
1. I will be visiting (my grandmother) over spring break this year.
This is a noun phrase because it consists of a modifier: "my" and a noun: "grandmother" and it functions as a direct object (it receives the action of the verb "visiting").
2. (The team decided) that Prabu will be their new captain.
This is <u>NOT</u> a noun phrase because it has a subject and a verb: "team" and "decided" respectively.
3. (Pizza with mushrooms and peppers) is my absolute favorite food.
This is a noun phrase working as a subject: it consists of a noun and its modifier: "with mushrooms and peppers" that adds detail to the noun, and it is the main thing being dealt with in the sentence.
4. The gardening club planted flowers and ferns (all around the school.)
This is <u>NOT</u> a noun phrase because it is not acting as a noun but as a single unit that gives further detail to the verb "planted" by indicating when the plants were planted. Therefore, it is an adverb phrase.