--charlie doesn't seem like the same person ---___so much in the war has made him more thoughtful

问题描述:

--charlie doesn't seem like the same person ---___so much in the war has made him more thoughtful
答案是his seeing 可是 having seen 为什不对?

作主语的通常是动词的ing形式,但这里不是完成式,而是强调一般情况.