1 The music will help (to relax).
2 I have found that lost watch.(改为一般疑问句).
Have you found that lost watch?
3 You should finish all your homework (in half an hour).(对划线部分提问)
How soon should I finish all my homework?
4 It has been famou for its theatres (since the early twentieth century).(对划线部分提问)
How long has it been famous for its theatres?
5 Seeing the huge glass ball falling through the darkness is exciting.(改为同义句)
It's is exciting to see the huge glass ball falling through the darkness.
6 多吃水果有益健康 .(翻译)
Eating more fruit is good for health.