What part of speech is "lake" in the phrase "The surface of the lake is very quiet"?

In the phrase "The surface of the lake is very quiet," "lake" functions as a noun. Nouns are words that represent people, places, things, or ideas, and they serve as the subject or object in a sentence. In this context, "lake" is specifically naming a large body of water, which is a tangible entity. It plays a vital role in the sentence by indicating what the surface being described (as quiet) belongs to. Therefore, identifying "lake" as a noun is accurate because it fits the definition of a noun by naming a specific thing in the world.