Not until he retired from teaching three years ago having a holiday abroad.
Ahe had considered
Bhad he considered
Che considered
Ddid he consider
网友回答
A. he had considered
B. had he considered
C. he considered
(答案→)D. did he consider
解析：Not until位于句首时句子要倒装，consider having a holiday abroad这个动作发生在retire之后，所以用一般过去时。
【考点】特殊句式—倒装。