What part of speech is the word type as in There are three types rocks?

The word "types" in the sentence "There are three types of rocks" is a noun.

Here's why:

* It names a thing: "Types" refers to a category or classification of rocks.

* It can be pluralized: The sentence uses the plural form "types."

* It can be modified: You can modify "types" with adjectives, like "different types" or "specific types."

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