Cars play an important role in modern life, but they ______ also cause many problems like air pollution.
#63554
A
should
B
can
C
must
D
will
推荐题目
He________sleep，although he tried to，when he got on such a hunt for an idea until he had caught it.
#62298
A
wouldn’t
B
shouldn’t
C
couldn’t
D
mustn’t
—Why，I didn’t get you on the phone.—We ________football on the playground when you phoned.
#62277
A
must be playing
B
must play
C
must have played
D
must have been playing
Today is Wednesday. He _____ be at home. He _____ be at school.
#76066
A
can't; can
B
can't; must
C
mustn't; must
D
mustn't; can
Days later, my brother called to say he was all right, but _______say where he was.
#63510
A
mustn’t
B
shouldn’t
C
wouldn’t
D
mightn’t
--- There is someone at the door. Who ______ it be? Is it the postman?--- No, it ________ be him. It’s just seven o’clock. It’s too early.
#75704
A
may, can’t
B
will, won’t
C
may, mustn’t
D
must, may not