I could have called you for help, but I your number.
A. couldn’t remember
B. didn’t remember
C. should have remembered
D. hadn’t remembered
网友回答
A. couldn’t remember
(答案→)B. didn’t remember
C. should have remembered
D. hadn’t remembered
解析：could have done 表示过去本可以做某事而没有，是一个与过去事实相反的虚拟语气，but后引出了一个过去事实,说明不能做的理由。故remember用一般过去时。