An adverb is a word that modifies a verb, adjective, or another adverb.
A verb is an action word (doesn't apply here)
An adjective is a describing word. Thing such as "Funny, Happy, Silly, Lively, and Oily are ADJECTIVES
Remember, an adverb must MODIFY an adjective, it can't BE an adjective.
The answer, using process of elimination, is ACTUALLY
For example:I didn't think he'd be like that, but he was actually funny!
Funny is the adjective, actually is the modifier, it further provides information for the word "funny"
Your answer is ACTUALLY
