Adverbs

Adverbs can tell you where, when, how, why and to what extent something happens.
There are several different classes of adverb (see above).
They are often formed from adjectives or nouns be adding the suffix -ly. 
For example: 
Quick becomes quickly, sudden becomes suddenly, intelligent becomes intelligently.
To form an adverb from adjectives ending in -y change the y to i before adding the -ly.
For example: 
angry becomes angrily, busy becomes busily.
To form an adverb from adjectives ending in -e drop the -e before adding the -ly.
For example:  
feeble becomes feebly, true becomes truly.
Some adjectives ending in -ly need no changes.
For example: 
heavenly.

                   Types of Adverbs

However there are exceptions.
For example:  
sly becomes slyly, shy becomes shyly.
Adverbs can modify adjectives
An adjective can be modified by an adverb, which precedes the adjective.
For example:-
That's really nice.
 
Adverbs can modify adverbs
Some adverbs can modify others. As with adjectives, the adverb precedes the one it is modifying.

For example:-
She did it really well.
Adverbs can modify nouns
Adverbs can modify nouns to indicate time or place.

For example:-
The concert tomorrow.
The room upstairs.

Adverbs can modify noun phrases
Some adverbs of degree such as quite, rather, so, such ... can modify noun phrases.

For example:-
We had quite a good time.
They're such good friends.

Adverbs can modify determiners, numerals and pronouns
Adverbs such as almost, nearly, hardly, about, etc., can be used:

For example:-
Nearly everyone, who was invited, came to the party.

Adverbs can modify sentences
Some adverbs modify a whole sentence, not just a part of one.

For example:-

Luckily the car sped in time. In this sentence luckily modifies the whole sentence, it shows that it was good luck that the car sped in time.