Every possible means ______ to prevent the air pollution, but the sky is still not clear.
#85598
A
has been used
B
have been used
C
is used
D
are used
推荐题目
More than one student _________ read the novels, which _________ written by David.
#86199
A
has, was
B
have, were
C
has, were
D
have, was
John,together with some of American soldiers who sent to Iraq， killed in a bomb explosion.
#86250
A
were;were
B
was;was
C
were;was
D
was;were
— Would you mind if I sing here?— . Look at the sign. It says “Be Quiet”.
#43859
A
Of course not.
B
Better not.
C
Not at all.
D
I don’t mind.