The traffic was busy on our way to the train station we caught the train on time at last

问题补充：

The traffic was busy on our way to the train station, we caught the train on time at last.

A. although

B. so

C. but

D. because

答案：

(答案→)A. although

B. so

C. but

D. because

解析：句意：在我们去火车站的路上交通非常繁忙，虽然最后我们按时赶上了火车。On one’s way to 在去……的路上，on time 按时；at last 最后；A. although 尽管、虽然；B. so因此；C. but但；D. because因为，根据句意故选择A。