Many accidents by careless drivers last year.A. are caused B. were causedC. have caused D

问题补充：

Many accidents by careless drivers last year.

A. are caused

B. were caused

C. have caused

D. will cause

答案：

A. are caused

(答案→)B. were caused

C. have caused

D. will cause

解析：本题是对被动语态的考察，主语accidents与谓语动词cause是被动关系，而且整体时态从yesterday可知是一般过去时。