Sir you should at the red light but you didn’t.A. stopB. have to stopC. have stoppedD.

问题补充：

Sir, you should at the red light, but you didn’t.

A. stop

B. have to stop

C. have stopped

D. not have stopped

答案：

A. stop

B. have to stop

(答案→)C. have stopped

D. not have stopped

解析：考察虚拟语气。句意：先生，你应该在红灯亮时停，但是你没有。表示对已发生的事情的虚拟用shouldn’t have done 故选C。