Modal verbs

Help me please, its correctly or not:

Could you do me a favour? I need some money.
I have never been able to write correctly since I was a child.
It was quite warm, so we could have breakfast in the garden.
Will you be able to lend me your car for the next weekend?
I want to do be able to do what I want not what I have to.
I have been able to see black clouds coming – it was going to rain.
I enjoy being able to do what I like.
I don’t have to do the shopping because I have already done it.
Did you mustn’t drive so fast? You almost had an accident!
I really had to study harder – I’ve got an exam next week.
At school we must go out to the schoolyard during breaks.
You mustn’t speak loudly in here, be quiet!