1.  So it makes up for the used fresh water.

2.  Firstly, all of us should used water economically, and never waste it any more.

3.  First, the population is rising so quickly that the used fresh water increases.

4.  It can help us to control the fresh water shortage, but save is not enough, now scientists are busy searching a good method to produce water, that is to clean the used water for reuse in this system, we won't use up our fresh water .

5.  As a result, some factories put the used water into river , and make it poisoned and can't be used again.

6.  Moreover, we May refresh used water and polluted water and make them to be used again.

7.  In addition, we should take advantage of the used water and change it into fresh water.

8.  Third, we can reuse the used water, which May help us to escape from the global shortage of water.

9.  The increase of the population, the increase of the used water of industry, these increase the use of the fresh water .