What part of speech denotes action or state being?

The part of speech that denotes action or state of being is a verb.

Here's why:

* Action verbs describe actions, like "run," "jump," "eat," "write."

* State of being verbs (or linking verbs) describe a state of being, like "be," "seem," "become," "appear." They connect the subject to a noun or adjective that describes it.

For example:

* Action verb: The dog ran across the park.

* State of being verb: The sky is blue.

Let me know if you'd like more examples!