Once environmental damage __________,选择

Once environmental damage __________, it takes many years for the system to recover.

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

 

[单选题]Once environmental damage ______, it takes many years for the system to rec

[单选题]Once environmental damage ___________, it takes many yearsfor the system to

[单选题]Once environmental damage ________,it will take many years for the system t

[单选题]Once environmental damage ______, it takes many years for the system to rec

[单选题]Once environmental damage( )，it takes many years for the system to recover.

[单选题]Once environmental damage( )，it takes many years for the system to recover.

[单选题]Once environmental damage( )，it takes many years for the system to recover.

[单选题]Once environmental damage( )，it takes many years for the system to recover.

[单选题]Once environmental damage_____, it takes many years for the system to recov

[单选题]Once environmental damage(),it takes many years for the system to recover.环