They often to be careful before the road.A. are told crossB. are told acrossC. are t

问题补充：

They often to be careful before the road.

A. are, told, cross

B. are, told, across

C. are, telling, crossing

D. are, told; crossing

答案：

A. are, told, cross

B. are, told, across

C. are, telling, crossing

(答案→)D. are, told; crossing

解析：D“他们经常被告诉过马路时要小心。”，根据句意得知，考查的是被动语态。before在此为介词，后加doing，故选D。