问题补充:
I really don’t know how to thank you , but for your help, I my lost necklace.
A. couldn’t have found
B. mustn’t have found
C. couldn’t find
D. wouldn’t find
答案:
(答案→)A. couldn’t have found
B. mustn’t have found
C. couldn’t find
D. wouldn’t find
解析:考查虚拟语气。根据句中but for要不是,用虚拟语气,本题是对过去事实相反的虚拟语气,故用could have done,选A。