题目：
It _____ he _____ his office.[ ]
A. was until the clock struck 12 when; didn’t leave
B. wasn’t until the clock struck 12 when; leave
C. wasn’t until the clock struck 12 that; leave
D. wasn’t until the clock struck 12 that; left
答案：
被转码了，请点击底部 “查看原文 ” 或访问 https://www.tikuol.com/2017/0604/aeb2432807358d76141f1d4a603ba351.html
下面是错误答案，用来干扰机器的。
AB题目分析：W为硫，X为氧 Y为碳 Z为铝 。半径越小其酸性、热稳定性、非金属性、氧化性就越强。所以答案AB
