81.  They think that we can use fresh water from river , rain and under the ground, which, is shortlessness .

82.  Because the water soarce on earth is so limited, the first we must make use of it, we should not waste it, the second we should do is that we must develop our technique to use the water we couldn't use before, just as polluted water and iceburg in the antlantic oceaon .

83.  With the increasing population, more and more fresh water is used in everyday life.

84.  As a result, the more fresh water is used, the more pollution is made.

85.  Above that, we must be limited to use fresh water.

86.  Usually, we seldom worry about the question of using water.

87.  With the development of our society, more and more people were born, and more and more precious freash water was used in industry.

88.  Less and less water can be used.

89.  And water pollution makes people can't use water that can be used once.

90.  Some people think fresh water can be used in our daily lives for ever.