Pleasant as they made it in Jiuzhaogou we felt tired after the long journey.A. to travel

问题补充：

Pleasant as they made it in Jiuzhaogou, we felt tired after the long journey.

A. to travel

B. travel

C. travelled

D. travelling

答案：

(答案→)A. to travel

B. travel

C. travelled

D. travelling

解析：本题考查非谓语动词。句中it为形式宾语，真正的宾语为to travel in Jiuzhaogou，故用不定式作形式宾语，选A。