【题目】Which of the following sentences is RIGHT?
A. Not until his son came back did he go to bed.
B. Not until his son came back he went to bed.
C. Not until did his son come back he went to bed.
D. Not until did his son come back did he go to bed.
在线课程【答案】A
【解析】
试题分析：句意：直到他儿子回来他才睡觉。not until位于句首句子主句倒装，从句部分不倒装。故选A.