his studies, he started travelling in China.
A. As soon as finish
B. As soon as finishing
C. Upon finishing
D. Upon finish
网友回答
A. As soon as finish
B. As soon as finishing
(答案→)C. Upon finishing
D. Upon finish
解析：句意，学习一结束，他就开始游历中国。分词动作“finish”和主语“he”之间是主动关系，故用现在分词作时间状语。