单选题 Not until I graduated from the college ______ how much time I had wasted.
A) have I realized C) I have realized
B) did I realize D) that I realized,

【正确答案】 B
【答案解析】句子意为：直到大学毕、我才意识到自己以前浪费了很多时间。本题测试考生对倒装句的掌握情况。当否定词放在句首时，句子要主谓倒装或部分倒装。