What is an adverb and how are adverbs used?

An adverb is a word or phrase that modifies or qualifies an adjective,verb,or other adverb or a word group,expressing a relation of place,time,circumstance,manner,cause,degree.

Adverbs are used to give you more information and are used to modify verbs, clauses and other adverbs.The difficulty with identifying adverbs is that they can appear in different places in a sentence. The simplest way to recognise an adverb is through the common ending-ly.

An adverb is a phrase for objects place and thing

I think it is sentence 4

Explanation: