It was not until the entrance exams were in sight that that I had so many books to cover and so many exercises to finish.
A. I realized
B. did I realize
C. had I realized
D. I had realized
网友回答
(答案→)A. I realized
B. did I realize
C. had I realized
D. I had realized
解析：此句是I didn't realize that I had so many books to cover and so many exercises to finish until the entrance exams were in sight．的强调句。not until…in sight位于强调结构中，realize就变成肯定，用过去时。