The witnesses(证人) of the accident said that the lorry very fast at the crossroads when th

问题补充：

The witnesses(证人) of the accident said that the lorry very fast at the crossroads when the accident happened.

A. is traveling

B. had travelled

C. was to travel

D. was travelling

答案：

A. is traveling

B. had travelled

C. was to travel

(答案→)D. was travelling

解析：考查时态。句意：这起交通事故的证人说这辆开车在事故发生时，正在高速行驶。结合语境可知从句描述的是过去正在进行的动作，故用过去进行时态。选D。