Adverb

An adverb is a word that modifies a verb, adjective, determiner, clause, preposition, or sentence. Adverbs typically express manner, place, time, frequency, degree and level of certainty; answering questions such as; how?, what way?, when?, where?, what extent?. This function is called the adverbial function, and may be realized by single words (adverbs) or by multi-word expressions (adverbial phrases and adverbial clauses).

Adverbs are regarded as one of the {parts of speech. However, the term "adverb" has come to be used as a kind of "catch-all" category, used to classify words with various types of syntactic behavior, not necessarily having much in common except that they do not fit into any of the other parts of speech.

• She sang loudly (loudly modifies the verb sang, indicating the manner of singing)
• We left it here (here modifies the verb phrase left it, indicating place)
• I worked yesterday (yesterday modifies the verb worked, indicating time)
• You often make mistakes (often modifies the verb phrase make mistakes, indicating frequency)
• He undoubtedly did it (undoubtedly modifies the verb phrase did it, indicating certainty)

Adverbs can also be used as modifiers of adjectives, and of other adverbs, often to indicate degree. Examples:

• You are quite right (the adverb quite modifies the adjective right)
• She sang very loudly (the adverb very modifies another adverb – loudly)