Only when he had done it ______ that he had made a mistake.
#82881
A
he then realized
B
did he realize
C
before
D
he realized
推荐题目
We read them ________; we remember them________. 
#84206
A
as young; as old
B
as younger; as older
C
when young; when old
D
when younger; when older
 ---How was the weather then? ---Hardly _____ off the plane when it started to rain.
#81637
A
I had stepped
B
had I stepped
C
I stepped
D
did I step
She hurriedly left the room without saying anything as if ____.
#79543
A
she angry
B
was angry
C
it was angry
D
angry