Adverbs describe a verb, an adjective or another adverbs. They are unchangeable, that also means that they do not care about gender or number of anything in the sentence.

Regular, derived (meaning derived from an adjective: see chapter 13.8) English adverbs describing verbs have the ending -ly.

He builds his house very slowly. They build their house rather quickly. We dance nicely together.

Other adverbs are not that easily recognised.

I think it's rather stupid to do so. You can't break into a well guarded home. He eats quite a lot.

Over there is a house.. Here it happened.

One thing is quite clear: the difference between adverbs and adjectives. Adjectives describe a noun. And they change according to the noun they are referring to. Have a look.