posted by Billy .
If "noisily" is an adverb in the following sentence, what is "mooing"?
The cows entered the barn mooing noisily.
"Mooing" is a present participle. See the -ing ending? Whenever you see one of those and there's no helping verb there to make it a complete verb, then the verbal is a present participle, serving as an adjective. So ... what noun is "mooing" describing?
The word, "mooing," is a participle, modifying the noun "cows." Participles are verb forms used as adjectives.
For more information about participles, check this site.