第26题: [单项选择]He led an attack on what ______ his own castle, and blew it up with dynamite! A. ought to be B. ought to have been C. should be D. seems to be 参考答案:B 答案解析:该题中ought to have been意思是“本应当是”,他向本应当是自己的城堡发动攻击,且用炸药将其炸毁。ought to have done不同于should have done的地方在于前者