Our classroom   _______   by us every day!
#44538
A
is cleaning
B
has cleaned
C
must clean
D
is cleaned
推荐题目
The light bulb ______ by Edison in the middle of the 1780s.
#44649
A
is invented
B
was invented
C
invented
D
invent
—Oh, this is really an old building.—Do you know when it        ?
#44645
A
has built
B
is built
C
was built
D
will be built