Not until I was standing on the edge of death how much I wanted to live.A. I realizedB. d

问题补充：

Not until I was standing on the edge of death how much I wanted to live.

A. I realized

B. did I realize

C. I had realized

D. had I realized

答案：

A. I realized

(答案→)B. did I realize

C. I had realized

D. had I realized

解析：考查倒装结构.当not until 等否定性词语谓语句首时,主句采用部分倒装.句意:直到我站在死亡边缘时,我才知道我是多么想活着.叙述的是在某个时间发生的动作,故用过去时态,选D.