1 They might be away for the weekend but I'm not sure.
2 You may leave now if you wish.
3 Could you open the window a bit, please?
4 He could be French, judging by his accent.
5 Can you play the piano?
6 Listen, please. You may not speak during this exam.
7 They can't still be out!
8 You couldn't smoke on the bus.
9 With luck, tomorrow could be a sunny day.
10 You might be right but I'm going back to check anyway.