Page 546
Adverb
An adverb is a word used to modify a verb, an adjective, or another adverb. An adverb tells how, when, where, why, how often, and how much.
Dad snores loudly.
(Loudly modifies the verb snores.)
His snores are really explosive.
(Really modifies the adjective explosive.)
Dad snores very loudly.
(Very modifies the adverb loudly.)