四、用所给单词的正确形式补全短文。
Subway is fast and comfortable. But do you feel 16. ______ when people play music or videos on the subway? It's not a problem now. There are some new 17. ______ for the subway in our city.
The first new rule is "no using loudspeakers (扬声器)". Subway riders must follow it when they 18. ______ the subway. They 19. ______ to use their earphones when they listen to music or watch movies on 20. ______ phones. If some people don't 21. ______ the new rule, the subway workers can stop them and take them to the police(警察).
There 22. ______ also some other rules. People cannot bring 23. ______ into the subway station. People cannot eat or 24. ______ in subway cars.
Many people 25. ______ and welcome the rules. And they think the rules can help subway riders. They also need the same rules on buses and trains.

16. unhappy 17. rules 18. take 19. have 20. their 21. follow 22. are 23. bikes 24. drink 25. understand