The part of speech that is primarily used to modify a verb, adjective, or other adverb. Adverbs can also modify prepositional phrases, subordinate clauses, and complete sentences. Adjective: adverbial.
Positions of an Adverb:
An adverb that modifies an adjective ("quite sad") or another adverb ("very carelessly") appears immediately in front of the word it modifies. An adverb that modifies a verb is generally more flexible: it may appear before or after the verb it modifies ("softly sang" or "sang softly"), or it may appear at the beginning of the sentence ("Softly she sang to the baby"). The position of the adverb may have an effect on the meaning of the sentence.