Question

　　　　about this computer program, a huge amount of time and energy　　　　.

A．Should I know; be saved

B．If I had known; can be saved

C．Had I known; would have been saved

D．Did I know; was saved

Answer 1

C

选C。考查倒装句和省略。含有should, had或were的虚拟条件句, 可省略if, 必须将should, had或were提到主语前。此处表示与过去事实相反的假设, 故选C。