问题补充：
―Thank you very much for giving me a hand when I was in trouble.
―Don’t mention it. I only did what anyone else in my place.
A. must do
B. might do
C. would have done
D. can have done
答案：
A. must do
B. might do
(答案→)C. would have done
D. can have done
解析：句意：―非常感谢您在我困难时给了我帮助。― 不客气。其他任何人在我这个位置都会这么做的。Did 这个动词提示what引导的宾语从句是对过去的推测。对过去的推测用C. would have done，或者could have done ; D. can have done形式不对，A. must do 和B. might do 是对现在的情况的推测。不合题意。
