问题补充:
—Tom, you look tired this morning. What’s wrong?
—I was so busy that I didn’t go to bed 12 o’clock last night.
A. until
B. when
C. though
D. unless
答案:
(答案→)A. until
B. when
C. though
D. unless
解析:考查点:连词辨析。解题思路:根据句意:汤姆,今天上午你看起来很累。怎么了?我非常忙以至于昨天晚上12点才上床睡觉。not…until…表示“直到……时候才……”。故选A。