问题
选择题
—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
答案
B
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。