What part of speech is gardening?

"Gardening" can be a few different parts of speech, depending on how it's used in a sentence:

* Noun: When it refers to the activity itself.

* Example: "I enjoy gardening."

* Gerund: When it acts as a verb, but functions as a noun.

* Example: "Gardening is my favorite hobby."

* Adjective: When it modifies a noun.

* Example: "She has a gardening book."

It's important to look at the context of the sentence to determine the specific part of speech.