The best way to prevent the air polluting _____ , but the sky is still not clear.
#102116
A
is used
B
are used
C
has been used
D
have been used
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Instead of telling the joke he _______, Crystal made up a new one.
#102101
A
made
B
has made
C
had made
D
would make
Those who said looking after children was an easy way to make money obviously ______ such a troublesome boy, she thought
#99392
A
hadn’t met
B
didn't meet
C
haven’t met
D
wouldn’t meet
—Do you know the Water Cube at all?—No, this is the first time I ________ here.
#99459
A
have been
B
came
C
was
D
am going
—I phoned you at 9 this morning but got no answer.—I am sorry. I _____ the bell. I _____ in the garden.
#101559
A
didn’t have heard, must have been
B
didn’t have heard, must be
C
didn’t hear, must have been
D
didn’t hear, must be