1. 用适当的情态动词完成句子。

1. （1） Since nobody gave him any help, he have done the research on his own.
3. （2） One of the few things you say about English people with certainty is that they talk a lot about the weather.
5. （3） Some people who don't like to talk much are not necessarily shy; they just be quiet people.
7. （4） When I was a child, I watch TV whenever I wanted to.
9. （5） They have arrived at lunchtime but their flight was delayed.
11. （6） —In case anyone come in my absence, tell him I will be back soon.

    —Sure, I will.

13. （7） —Will the chairman come here by train?

    —He should, but he not. He enjoys driving himself.

15. （8） Parents are doing all they to help their children achieve their ambitions.
17. （9） —I have coffee to refresh myself recently.

    —Is that so? If you , make sure you limit it to one cup a day.

19. （10） You are always throwing things about. How I know where you've left your key?