问题补充：
It was back home after the experiment.
A. not until midnight did he go
B. until midnight that he didn’t go
C. not until midnight that he went
D. until midnight when he didn’t go
答案：
A. not until midnight did he go
B. until midnight that he didn’t go
(答案→)C. not until midnight that he went
D. until midnight when he didn’t go
解析：考查强调句的特殊句型：It’s not until ….that…,直到…才…,值得注意的是not until不是在句首，后面不能倒装，句意：直到午夜他才做完实验回家。选C。
