问题补充:
Only after the plane had taken off that he missed his parents so much.
A. he found
B. he had found
C. did he find
D. was he found
答案:
A. he found
B. he had found
(答案→)C. did he find
D. was he found
解析:句意:只有当飞机起飞后,他才发现他是多么想念父母。考查Only引导从句放在句首时,用部分倒装。根据句意该句为过去时态。