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 or another adverb 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 , or it may appear at the beginning of the sentence. The position of the adverb may have an effect on the meaning of the sentence.
Functions of an Adverb:
Adverbs typically add information about time (rarely, frequently, tomorrow), manner (slowly, quickly, willingly), or place (here, there, everywhere) in addition to a wide range of other meanings.