---Why is the classroom so dirty? --- Sorry, sir. It ______ yesterday. We forgot to do it. 
#44831
A
doesn’t clean
B
didn’t clean
C
isn’t cleaned
D
wasn’t cleaned
推荐题目
The man is very ill and he has _______.
#44621
A
operate on
B
to be operated on
C
to operate
D
being operated on
—Where did you go last night?-I _______to go to Lily’s birthday party.
#44950
A
have been asked
B
have asked
C
asked
D
was asked
The sick boy ____________ to hospital by the police yesterday.
#44521
A
is taken
B
was taken
C
takes
D
took