【题目】— Mary, how did your Math test go?
— I had thought I ________, but in fact I came in the top 10 in my class.
A.should have failed
B.couldn't have failed
C.might have failed
D.shouldn't have failed

【答案】C
【解析】句意：—Mary，你的数学测试怎么样？—我认为我可能失败了，但是实际上我在班里在前十名。might have done sth.表示对过去发生的事情的猜测或担心，意思是“或许会……”，而事实上不一定如此。故选C。