When adverbs modify verbs (or verbals), they nearly always answer one of these questions:
Sometimes phrases or clauses are used as adverbs. They answer questions like those above, as well as these:
When adverbs modify adjectives or other adverbs, they usually qualify or intensify the meaning of the word they modify.
Be careful not to use adjectives in place of adverbs, even if you are accustomed to hearing such usage in casual or nonstandard speech.
Adverbs (smoothly, efficiently) must be used to modify the verb runs.
Only an adverb (really) can be used to modify an adjective (slim).
Exercise: Adjectives and adverbs 1
Exercise: Adjectives and adverbs 2
Exercise: Adjectives and adverbs 3
verb A word that expresses action (jump, think) or being (is, was, seems). A sentence's verb is composed of a main verb possibly preceded by one or more helping verbs.
verbal A verb form that functions as a noun or an adjective, not as the main verb of a clause. Verbals include infinitives (to sing), present participles (singing), and past participles (sung).
adjective A word that modifies or describes a noun or pronoun: lame, old, rare, beautiful; also the articles a, an, the.