单项选择题

Most environmental problems exist because adequate measures for preventing them ______ taken in the past.

A．was not
B．were not being
C．were not
D．was no to be
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单项选择题
The output of consumer products has increased ______ this year.
A．exceedingly
B．dramatically
C．hugely
D．extraordinarily
单项选择题
The current ______ is towards more part-time employment.
A．direction
B．trend
C．situation
D．position
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