Is is an noun adjective verb or adverb?

"Is" is a verb. It is the present tense form of the verb "to be."

Here's how you can tell:

* It expresses an action or state of being. In a sentence, "is" usually connects a subject to a predicate (describes something about the subject).

* It can be used as the main verb in a sentence. For example, "The sky is blue."

Let me know if you'd like more examples!