1.  As a student, we must put weekends to good use.

2.  How to put weekends to good use?

3.  So I must put weekends to good use.

4.  So I can put my two-day weekend to good use.

5.  We can make good use of our knowleges in the socity .

6.  We should make good use of these chances.

7.  On the other hand, we should try our best to improve the method of converting sea water into fresh water, so that the sea water can be made good use of.

8.  If we all realize the importance of fresh water and make good use of it, it can contribute our society a lot.

9.  We should make good use of each drop of water.

10.  Firstly, we should make good use of the fresh water.