—You ought to have made an apology to Tom yesterday evening．
—Yes, I know I ．
A. ought to have
B. have to
C. should
D. must have
网友回答
(答案→)A. ought to have
B. have to
C. should
D. must have
解析：考查情态动词。Should have done = ought to have done本应该做某事而实际上没有做。句意：昨天晚上你本应该向汤姆道歉的。是的，我知道我本应该向他道歉。所以选A，ought to have后省略了made an apology to him。