题目内容
（请给出正确答案）
Once environmental damage __________, it takes many years for the system to recover.
A) has done B) is to do C) does D) is done
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更多“Once environmental damage ____…”相关的问题
A.Evaluate environmental threats.
B.Assess the physical security facility,
C.Assess the communications network security.
D.Develop a personnel security program.
A.air pollution
B.acid rain
C.water pollution
D.large oil spill
The environmental problems ________________(没有他们在报告中说得那么严重)
A.Located in medium and low latitudes， China's sea areas have advantageous natural environmental and resource conditions.
B.China's sca areas locate in medium and low latitudes; there are advantageous natural environmental and resource conditions.
C.Located in medium and low latitudes， China' 8 sea areas are full of advantagcous natural envi-ronmental and resource conditions.
Do you need ______ at once？
A、to go
B、go
C、going
D、goes
