1.  Example: doing homework, doing housework, even clearing up my school-bad ... This test paper was done so bad, the important reason was this .

2.  From the picture we can see, in 1960 Life expectancy in developing countries was 40 years old and improved to 60 years old in 1990.

3.  Meanwhile Infant mortaility in developing countries was diclined from 200 deaths per 1,000 births in 1960 to 100 deaths per 1,000 births in 1990.

4.  These changes taken place result from two important reasons.

5.  But the most important reasons is that the developing countries have rapidly developed and will also develop.

6.  I think, the important reason is the income of people in the developing countries has raised in 30 years.

7.  This is the important reason that why Developing countries gain health condition.

8.  But the important reason for shortage of fresh water is water polution .

9.  The most important reason is that health gains in developing countries.

10.  The other important reason is the development of the medical .