Question

You mustn't cross the street while the red traffic lights are on．Which of the following is the same in meaning？

1. A.
   You must walk slowly across the street when the red traffic lights are on．
2. B.
   You can't go across the street before the traffic lights change to red．
3. C.
   You don't have to wait when you want to go to the other side of the street though the traffic lights remind you not to do so．
4. D.
   Don't go across the street before the traffic lights change to green．

Answer 1

D
分析：原句是“不许可”的意思，you mustn't do可以改为you can't do，但B项的意思不对。D项Don't go＝You mustn't go，而且意思一致。(延伸)肯定祈使句可以转换成You must do…如：Put your bike here．＝You must put your bike here．否定祈使句可以转换成You mustn't do…如：Don”t put your bike here．＝You mustn't put your bike here．