—Why didn’t you try your best to get on the bus?—I tried to but I could it started mov

问题补充：

—Why didn’t you try your best to get on the bus?

—I tried to , but I could, it started moving.

A. before

B. when

C. until

D. after

答案：

(答案→)A. before

B. when

C. until

D. after

解析：考查连词。before 在什么之前，还没来得及，when 当什么时候，until 直到，after 在什么之后，句意：你为什么不努力上公交车呢？我努力了，但是我还没来得及上车，车就开始走了。所以选A。