Last summer,big floods occurred in both the south and north of China.They were the most serious ones in this century.They caused great loses.Fields were ruined,houses were washed away and many people became homeless.

　　There are three reasons for the floods.First,it had kept raining for months.Secondly,many forests had been cut down and the soil was washed away.Finally,some lakes had been turned into fields,which seriously blocked the waterways.

　　Now,some measures have been taken to prevent floods from happening again.The trees along the rivers have been protected;old dams have been rebuilt and some fields have been turned  back into lakes again.