What part of speech is regret?

"Regret" can be several parts of speech, depending on how it is used in a sentence:

* Noun: This is the most common usage. It refers to the feeling of sorrow or remorse for something done or left undone.

* Example: "He felt a deep regret for his actions."

* Verb: This usage means to feel sorrow or remorse.

* Example: "I regret telling her that."

* Adjective: This usage means "feeling regretful or sorrowful."

* Example: "She had a regretful look on her face."

So, to know what part of speech "regret" is, you need to look at how it is used in the sentence.