1.  It is showed that our average lifes are longer and infant mortaility is lower than before.

2.  In 1960, the average life expectancy of developing countries is 40 years old.

3.  But in 1990, the average life expectancy of developing countries is 60 years old.

4.  But in 1990, the average infant mortaility of developing countries is one tenth.

5.  The average age has improved about 20-year-old .

6.  In 1960 the average life expectancy was 40 years old.

7.  as time went on, the institution changes much in 1990, the average life expetancy rised to sixty years old and infant mortality was down to ten percent.

8.  The overcrowed population makes the average volume of water is Decreasing.

9.  Scientists have draw a conclusion from many facts that the average people's use fresh water is Decreasing.

10.  The increasing of population and much water used by industries Decrease the average fresh water consume .