15. While he __________ in Europe, he __________ some photographs of many universities.

　 A. traveled; was taking　　　　　　　　　　 B. was traveling; took

　 C. traveled; had taken　　　　　　　　　　 D. was traveling; had taken

14. __________ it comes to traffic rules, I often come across such cases __________ the local drivers obviously know them but won’t follow them.

A. When; when　 　　 B. That; when　　　　　 C. When; which　　　 D. When; where

13. - Sorry for having kept you waiting. But for the traffic jam, I __________ 20 minutes earlier.

-Never mind. I haven’t been waiting that long.

A. arrived　　　 　　 B. would have arrived　　 C. would arrive　　　　 D. had arrived

12. No sooner __________ they arrived at the railway station __________ the train left.

　 A. have; when　　 　　　　　 B. had; when　　　　　 C. had; than　 　　　　　　　　　 D. have; than

11. He focused on his test papers, __________ never __________ the same mistakes.

A. determined; to repeat　　　　　　　　 　　　　 　　B. being determined; to repeat

C. determined; repeating　　　　　　　　　 　　　 　　D. determining; repeating