What part of speech shows action or state being?

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

Here's why:

* Action: Verbs describe actions, both physical and mental. Examples: *run*, *jump*, *think*, *write*.

* State of being: Verbs also express a state of existence or condition. Examples: *is*, *are*, *was*, *were*, *seems*.

Let me know if you have any other questions!