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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I ____  to send him a telegram to congratulate him on his marriage, but I ____ it.
#104845
A
hoped, hadn’t managed
B
has hoped, didn’t manage
C
hope, don’t manage
D
had hoped, didn’t manage
— Can we meet tomorrow afternoon?—Not in the afternoon, I’m afraid.I         .
#102908
A
will be working
B
am going to be
C
am about to work
D
will work
Salley________Beijing for Shanghai and________there ever since. You can go and pay her a  visit on your way to Hangzhou. 
#104697
A
has left; worked
B
left; worked
C
has left; had worked
D
left; has worked