All possible means ____ to prevent the air pollution, but the sky is still not clear. 
#100326
A
is used
B
has been used
C
are use
D
have been used
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Tim ____since he lost his job three weeks ago.
#101002
A
had been unemployed
B
was unemployed
C
has been unemployed
D
has unemployed
 —Why don’t we choose that road to save time?—The bridge to it _____________.
#100093
A
has repaired
B
is repaired
C
is being repaired
D
will be repaired