问题补充:
---He ought to have been warned of the danger.
---, but he wouldn’t listen to me.
A. He did
B. He should
C. He ought to
D. He was
答案:
A. He did
B. He should
C. He ought to
(答案→)D. He was
解析:考查特殊句式。So + 主语+ 助动词/系动词/情态动词,表示“的确如此”。根据答语后半句可知空处表示他的确被警告了,因此选D。