Cars play an important role in modem life, but they       also cause many problems like air pollution.
#87845
A
should
B
can
C
must
D
will
推荐题目
   We were very busy yesterday. Otherwise we _____part in the discussion.
#88150
A
would take
B
did take
C
had taken
D
would have taken
This is his only request that the room ______ after being used.
#87611
A
is cleaned
B
will be cleaned
C
would be cleaned
D
be cleaned
The doctor from Shanghai recommended that the patient ___________.
#87329
A
is not operated
B
should operate on
C
not be operated on
D
was not operated