Our teacher asked us the bus after the trip.A. to cleanB. cleanedC. cleaningD. clean

问题补充：

Our teacher asked us the bus after the trip.

A. to clean

B. cleaned

C. cleaning

D. clean

答案：

(答案→)A. to clean

B. cleaned

C. cleaning

D. clean

解析：叫某人做某事通常写成ask sb to do sth，故选A。意思为老师叫我们旅行之后把公共汽车打扫一下，故选A。