11.  Industrial water should be cleaned before sending into rivers.

12.  It is caused mainly by the pollution rising , the industrial water rising and the pollution.

13.  We should controll the population to incease and save the industrial water.

14.  With the increase of the population in the world and the increase in industrial water, more and more water are needed.

15.  Industrial water is required more and more.

16.  Growing of population, increasing in industrial water and water pollution all result in the shortage of fresh water.

17.  The need of industrial fresh water is also increasing.

18.  For one thing, with the progress of industry, the industrial water is increased sharply.

19.  Second, by the increasement of industrial water, the fresh water Decreases faster.

20.  Second, the needs of the industrial water is increasing.