In the sentence "The dog barked loudly," what part of speech is "barked"?

In the sentence "The dog barked loudly," the word "barked" serves as a verb. Verbs are action words that describe what the subject of the sentence is doing, and in this case, "barked" indicates the action performed by the subject, which is "the dog." It tells us what the dog did, making it the main action of the sentence.

When determining the part of speech, it's essential to recognize the role each word plays. Here, "barked" is not describing a quality or state (adjective), nor is it a person, place, thing, or idea (noun). Additionally, it is not providing more information about how the action is performed (adverb), which is the role of "loudly" in this sentence. Therefore, identifying "barked" as a verb accurately reflects its function as the action word in the context provided.