Could:
1.Could you use a computer when you were 3?
No, I couldn't.
2.Could you dance when you were five?
No, I couldn't.
Can:
1. Can you swim?
Yes, I can.
2. Can you play the piano?
No, I can't.
Will be able to:
1. Will you be able to play the piano in a month?
Yes, I will.
2. Will you be able to dance in a week?
No, I won't.
Sper ca te-am ajutat!