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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(2013·高考湖南卷)—I don’t understand why you didn’t go to the lecture yesterday afternoon.—I’m so sorry.But I________my homework.
#99695
A
had done
B
was doing
C
would do
D
am doing
After school we went to the reading-room to do some reading, only to be told that it .
#99303
A
was decorated
B
had decorated
C
had been decorating
D
was being decorated
---- You haven’t got the textbook for my chemistry course yet. ---- I know, and we _____ to get it for the last 5 weeks.
#104715
A
will have been trying
B
have been trying
C
will be trying
D
had tried
Seeing the road ________ with snow, they had to stay at home, watching TV and drinking coffee.
#103051
A
blocking
B
blocked
C
to block
D
to be blocked
—I called you many times yesterday morning, but I couldn’t get through. —Oh. My brother ______on the phone all the time!
#103592
A
was talking
B
has been talking
C
has talked
D
talked