-- I didn't realize how popular the restaurant was until I made a reservation the other day.
-- I beg your pardon, but when ?
A. was you realized it
B. it was that you realized it
C. you realized it
D. was it that you realized it
网友回答
A. was you realized it
B. it was that you realized it
C. you realized it
(答案→)D. was it that you realized it
解析：本句考查强调句，正常的语序是：it was when that you realized it，因为是问句，所以把when提到前面去了。句意：——直到那天我定了饭，我才知道这家饭店是多么的出名了。——你再说一遍，你究竟是什么时候知道的。