I didn’t know your telephone number; otherwise I you long ago.A. had rungB. have rungC.

问题补充：

I didn’t know your telephone number; otherwise, I you long ago.

A. had rung

B. have rung

C. would have rung

D. would ring

答案：

A. had rung

B. have rung

(答案→)C. would have rung

D. would ring

解析：考查隐含的虚拟语气：句意：--我不知道你的电话号码，否则，我早就会给你打电话了。这里的Otherwise相当于=if I had known your phone number.，所以主句用would have done，选C。