(2013·高考江苏卷)I should not have laughed if I you were serious.
A. thought
B. would think
C. had thought
D. have thought
网友回答
A. thought
B. would think
(答案→)C. had thought
D. have thought
解析：选C。句意：“如果我当时想到你是认真的，我就不会笑了。”根据主句中should not have laughed 可知，本句所讲的与过去事实相反。if引导非真实条件句表示与过去事实相反时，从句谓语结构为had done。