50.( ) A. chance
B. way
C. time
41-45BCAAB 46-50CABBC
(C)
Everyone knows people need water． But do you know just how __41 _water is to
living things ?
Maybe you feel lucky__42 _your life
isn’t hard . But it doesn’t mean that you don’t have to worry about water．We all face serious water __43 _．
One of them is water pollution．All kinds of things from cars , factories , farms and
homes __44 _our rivers , lakes and oceans dirty . Polluted water is very
bad __45_people to drink . And dirty water is bad for fish, __46 _．Now , 34 percent of all kinds of fish are dying out .
How do cars and factories make our water
dirty ? First，they pollute the air．Then，when it__47 _，the rain water comes down and makes our drinking water
dirty．Dirty rain，called
acid rain，is also bad for plants，animals and buildings．
__48 _people have made wells to get
clean water from underground . But there still isn’t enough . Scientists__49
_ that in 30 years, more than half of the people in the world won’t have
enough clean water .
When we don’t take care of our water，we are hurting everyone．It’s time
to start learning how to save more water for__50 _ and our children．