Every possible means ___ to prevent the air pollution, but the sky is still not clear．
#101596
A
is used
B
are used
C
has been used
D
have been used
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The gasoline . Let’s fill the car up at the next gas station.
#100795
A
is running out
B
has run out
C
is being run out
D
has been run out
—Lucy, tell me about your trip to the beach.—Awful! There ________ too many holidaymakers.
#99474
A
had been
B
were
C
would be
D
have been
In the past ten years, the ____mountain climber ____ a lot from his own adventurous _______
#102427
A
experienced; experienced; experience
B
experience; experienced; experiences
C
experienced; has experienced; experiences
D
experience; has experience; experience
By the time I see you again, I _______ from that school.
#100006
A
have graduated
B
graduated
C
will have graduated
D
graduate