In order to keep the balance of ecosystem, every possible means _______to deal with the problems of the over-exploiting of natural resources. 
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A
has tried
B
has been tried
C
have taken
D
have been taken
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A new cinema ______ here. They hope to finish it next month. 
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A
will be built
B
is built
C
has been built
D
is being built
When you get the paper back,pay special attention to what______.
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A
have marked
B
have been marked
C
had marked
D
had been marked