Our classroom   _______   by us every day!
#44538
A
is cleaning
B
has cleaned
C
must clean
D
is cleaned
推荐题目
The mayor is happy to find that many trees _______ in our city last year. 
#44369
A
plant
B
were planted
C
planted
D
are planted
Bikes ______ in the 1880s and they ______ traveling around.
#45063
A
were invented; were used as
B
were invented; are used for
C
was invented; was used for
D
invented; are used to
  The girl in black trousers _____often noticed ______the teachers’ office.
#44412
A
are; entering into
B
are; entering
C
is; to enter into
D
is; to enter