1. When I was a kid I could jump for hours. 
2.Can you do me a favour? I need some money. 
3. I have never been able to write correctly since I was a child. 
4. It was quite warm, so we cold have breakfast in the garden. 
5. Will you be able to lend me your car for the next weekend? 
6. I want to be able to do what I want not what I have to. 
7. I could see black clouds coming – it was going to rain. 
8. I enjoy to be able to do what I like.

2. Fill in with have to, must, don’t have to, mustn’t.
1. You mustn’t lean out of the window. 
2. I don't have to do the shopping because I have already done it. 
3. Did you have to drive so fast? You almost had an accident! 
4. I really must  study harder – I’ve got an exam next week. 
5. At school we must (mustn't) go out to the schoolyard during breaks. 
6. You mstn't speak loudly in here, be quiet!

2)can
3)been
4)cold
5)be
6)be
7)could
8)to be

2)do not have
3) have to
4)must 
5)must 
6)must not