By the time my parents reached home yesterday, I __________ the dinner already.
#36344
A
had cooked
B
cooked
C
have cooked
D
cook
推荐题目
While the boy ______ down the street, the UFO _____ . 
#41890
A
was walking; was landing
B
walked; landed
C
was walking; landed
D
walked; was landing
Look, so many people are running out of the station. I wonder what ________.
#36284
A
is happened
B
was happening
C
is happening
D
had happened