21.  It is a also our responsibility to call up other people to make good use of fresh water.

22.  In my opinion, First of all, we shall make good use of water.

23.  Above of all, we should make good use of every drop of water rather than waste it.

24.  Second, we must make good use of fresh water.

25.  I think, the first most of all, don't waste water any longer and save water to make good use of it.

26.  Third, we must make good use of fresh water.

27.  To solve the problem, first, we must do our best to make good use of every drip of the fresh water.

28.  In my opinion, first, we must use water economically, we must make good use of the fresh water .

29.  First, we should control the population; Second, we should save water; Third, we should make good use of the fresh water in the industry.

30.  First of all, everyone who want our future bright should put the limited fresh water to good use.