more and more people have realize we won't have cleaner water to drink unless something __soon

is done.越来越多的人意识到如果不尽快做些什么的话,我们将没有干净的水喝了.但是答案to be done……那就按照答案来吧，我个人觉得is done是对的，to be done...我的语法不好的说。反正就是用do这个单词吧。