Once environmental damage ________,it will take many years for the system to ...

admin2020-12-24  19

问题 Once environmental damage ________,it will take many years for the system to recover.

选项 A. is to do
B. does
C. has done
D. is done

答案D

解析环境一旦遭到破坏需要很多年才能恢复过来。
转载请注明原文地址:https://ti.zuoweng.com/ti/YNB8KKKQ