单项选择题

Scientists say it may be ten years ______ this medicine was put to use.

A．since
B．before
C．after
D．when
<上一题 目录 下一题>
热门 试题

单项选择题
They are often ______ caring more about animals than human beings.
A．accused of
B．accused with
C．charged of
D．charged for
单项选择题
We've worked out the plan and now we must put it into ______ .
A．fact
B．reality
C．practice
D．deed
相关试题