单项选择题

Every possible means ______ to prevent the air pollution, but the sky is still not clear.

A. is used
B. are used

C. has been used
D. have been used
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单项选择题
No one knew of the manager's intention to leave ______ his secretary.
A. including to
B. except
C. adding to
D. in addition
单项选择题
The film ______ next week is Men in Black Ⅲ.
A. showing
B. to be shown

C. being shown
D. to have been shown
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