the form of rain.Then it goes to one or two places.It might leak(4)
through the soil,then go into the natural pools,lakes or rivers underground.It might(5)
steam and go up into the sky,becoming clouds. There is a(6)
with this recycling system.It is a balance(平衡) that can be easily(7)
by people.Nature's recycling system can work (8)
only if people work with the system-not against it.The waste water from home and factories(9)
mix with drinking water,or people would get(10)
because of drinking dirty water.But we can't stop dirty water running into lakes or rivers,so water pollution is very dangerous to humans' health.We should not break down this system.