高等教育 / 新发展英语综合教程（二）
The following tells us how to reuse the used water. Which is the right order of the passage?
A.to have the used water filtered
B.to put chemicals in it
C.to pipe it to the users
D.to pipe the used water to be purified to a factory
A.to have the used water filtered
B.to put chemicals in it
C.to pipe it to the users
D.to pipe the used water to be purified to a factory
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