题干
—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.
—I was so busy that I didn’t go to bed _____ 12 o’clock last night.
A：until
B：whe
C：though
D：unle
答案(点此获取答案解析）
A
