It´s important that while you are learning you have some fun, So we put some jokes where you can see the use of  Modal Verb. So enjoy it.

Also you can learn about modal verbs with music :

    DONT WORRY, BE HAPPY

Here's a little song i wrote,
you might want to sing it note for note,
don't worry, be happy

in every life we have some trouble,
when you worry you make it double
don't worry, be happy

dont worry be happy now
dont worry be happy
dont worry be happy
dont worry be happy
dont worry be happy
aint got no place to lay your head,
somebody came and took your bed,
don't worry, be happy

the landlord say your rent is late,
he may have to litagate,
dont worry (small laugh) be happy,

look at me im happy,
don't worry, be happy

i give you my phone number,
when your worried, call me,
i make you happy

don't worry, be happy

aint got no cash, aint got no style,
aint got no gal to make you smile
but don't worry, be happy

cos when you worry, your face will frown,
and that will bring everybody down,
so don't worry, be happy

don't worry, be happy now...

don't worry, be happy
don't worry, be happy
don't worry, be happy
don't worry, be happy

now there this song i wrote
i hope you you learned it note for note
like good little children

dont worry be happy

listen to what i say
in your life expect some trouble
when you worry you make it double
dont worry be happy
be happy now

dont worry, be happy
dont worry, be happy
dont worry, be happy
dont worry, be happy
dont worry
dont worry be happy
don't worry, don't worry, don't do it,
be happy,put a smile on your face,
don't bring everybody down like this

don't worry, it will soon pass whatever it is,
don't worry, be happy,
i'm not worried

THE BEATLES -IF I FEEL

If I fell in love with you

Would you promise to be true

And help me understand

Cos I've been in love before

And I found that love was more

Than just holding hands

If I give my heart to you

I must be sure

From the very start

That you would love me more than her

If I trust in you oh please

Don't run and hide

If I love you too oh please

Don't hurt my pride like her

Cos I couldn't stand the pain

And I would be sad if our new love was in vain

So I hope you see that I

Would love to love you

And that she will cry

When she learns we are two

Cos I couldn't stand the pain

And I would be sad if our new love was in vain

So I hope you see that I

Would love to love you

And that she will cry

When she learns we are two

If I fell in love with you

 SNOW PATROL-CHASING CARS

WELL DO IT ALL

EVERYTHING

ON OUR OWN

WE DONT NEED

ANYTHING

OR ANYONE

IF I LAY HERE

IF I JUST LAY HERE

WOULD YOU LIE WITH ME AND JUST FORGET THE WORLD?

I DONT QUITE KNOW

HOW TO SAY

HOW I FEEL

THOSE THREE WORDS

ARE SAID TOO MUCH

THEYRE NOT ENOUGH

IF I LAY HERE

IF I JUST LAY HERE

WOULD YOU LIE WITH ME AND JUST FORGET THE WORLD?

FORGET WHAT WERE TOLD

BEFORE WE GET TOO OLD

SHOW ME A GARDEN THATS BURSTING INTO LIFE

LETS WASTE TIME

CHASING CARS

AROUND OUR HEADS

I NEED YOUR GRACE

TO REMIND ME

TO FIND MY OWN

IF I LAY HERE

IF I JUST LAY HERE

WOULD YOU LIE WITH ME AND JUST FORGET THE WORLD?

FORGET WHAT WERE TOLD

BEFORE WE GET TOO OLD

SHOW ME A GARDEN THATS BURSTING INTO LIFE

ALL THAT I AM

ALL THAT I EVER WAS

IS HERE IN YOUR PERFECT EYES, THEYRE ALL I CAN SEE

I DONT KNOW WHERE

CONFUSED ABOUT HOW AS WELL

JUST KNOW THAT THESE THINGS WILL NEVER CHANGE FOR US AT ALL

IF I LAY HERE

IF I JUST LAY HERE

WOULD YOU LIE WITH ME AND JUST FORGET THE WORLD?

You can practice what you learn in this blog in the next pages  there are many exercises to do .
http://www.nonstopenglish.com/allexercises/grammar/grammar-modal_verbs.asp 
http://www.english-test.net/esl/learn/english/grammar/ei049/esl-test.php 
http://www.advanced-english-grammar.com/modal-verb-exercises.html 

http://www.autoenglish.org/modalverbs.htm 

Modal Verbs

Here's a list of the modal verbs in English:

can	could	may	might	will
would	must	shall	should	ought to

Modals are different from normal verbs:

1: They don't use an 's' for the third person singular.
2: They make questions by inversion ('she can go' becomes 'can she go?')
3: They are followed directly by the infinitive of another verb (without 'to')

Probability:

First, they can be used when we want to say how sure we are that something happened / is happening / will happen. We often call these 'modals of deduction' or 'speculation' or 'certainty' or 'probability'.

For example:

• It's snowing, so it must be very cold outside.
• I don't know where John is. He could have missed the train.
• This bill can't be right. £200 for two cups of coffee!

Ability

We use 'can' and 'could' to talk about a skill or ability.

For example:

• She can speak six languages.
• My grandfather could play golf very well
• I can't drive

Obligation and Advice

We can use verbs such as 'must' or 'should' to say when something is necessary or unnecessary, or to give advice.

For example:

• Children must do their homework.
• We have to wear a uniform at work.
• You should stop smoking.

Permission

We can use verbs such as 'can', 'could' and 'may' to ask for and give permission. We also use modal verbs to say something is not allowed.

For example:

• Could I leave early today, please?
• You may not use the car tonight.
• Can we swim in the lake?

Habits

We can use 'will' and 'would' to talk about habits or things we usually do, or did in the past. 

For example:

• When I lived in Italy, we would often eat in the restaurant next to my flat.
• John will always be late!

Also you can watch this video in order to understand the meaning and use of modal verbs.