—Henry doesn’t seem like the same person.
— so much in the war has made him more thoughtful.
A. For him to see
B. His seeing
C. Having seen
D. To be seeing
网友回答
A. For him to see
(答案→)B. His seeing
C. Having seen
D. To be seeing
解析：很明显答语在结构上缺少主语。To do 与-ing都可充当主语，但 to do充当主语多表示某一具体的动作，且多表将来。故选B。