shall和should造句

1. Shall I turn off the light before I leave?

在我离开之前，我应该关灯吗？

2. She should be back by now.

她现在应该已经回来了。

3. You should have finished your homework by now.

你现在应该已经完成作业了。

4. He shall not pass the exam if he doesn't study hard.

如果他不好好学习，他不能通过考试。

5. You shall not touch the stove.

你不准碰炉子。