Ответ:
2 If Sheila hadn't lost her keys, she could have got in.
3 If Paul hadn't seen a shooting star, he wouldn't have made a wish.
4 If Billy had studied, he wouldn't have failed the exam.
5 If Sam hadn't gone out, his camera wouldn't have been stolen.
6 If she had been in the play, she would have got a prize.
7 If he hadn't broken amirror, he wouldn't have had seven years' bad luck.
8 If the director hadn't seen him, he wouldn't have made him a star.
#12
2 Uncle Bill asked us where our prents were.
3 Dad asked if I would help him carry the box.
4 Mum asked me what time I would be home.
5 he asked her if she could play the guitar.
6 David asked Janet who had been at the door.
7 they asked us where the post office was.