Can I help you?
I can't do this!It's very difficult!
Can she dance?
He  can't speak English very well! He's Spanish.
Can you ask the waiter, please?
You can't sing, can you?
I can't talk to you now! I'm busy!
Where can I find her?

E por aí vai...
Espero ter ajudado =)

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Oi! ^-^
I can 
You can 
He can 
She can 
It can 
We can 
You can 
They Can 

I can't / I cannot 
You can't / You cannot 
He can't / He cannot 
She can't / She cannot 
It can't / It cannot 
We can't / We cannot 
You can't / You cannot 
They can't / They cannot 

Can I...?
Can you..?
Can he...? 
Can she...? 
Can it...? 
Can we...? 
Can you...?
Can they...? 

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