Taking away a city's rubbish is a big job. Every day trucks come into a city to collect it. Most rubbish is made up of things we can't eat or use. If we kept these things, we would soon have a mountain of rubbish.
In some cities the rubbish is collected and taken outside of city to a dump (垃圾场). Often the city dump is placed where the ground is low or there is a big hole. The kitchen rubbish is broken into small pieces and sent into thesewagesystem (系统). The sewage system takes away the used water from toilets, bathtubs (浴缸) and other places.
To keep mice and flies away, some earth is used to cover the newly dumped rubbish. Later, grass may be planted on the rubbish-filled land. Finally, a house or a school may be built there, and then you'd never know that this had once been an old rubbish dump.
In other cities the rubbish is burnt in special places. The fire burns everything except the metal. Sometimes the metal can be used again in factories where things are made of metal. The food parts of rubbish are put in special piles (堆) and they slowly change into something that looks like black earth. It is rich with the kinds of things that feed plants and help them grow.
You can most probably read the passage in _________.
A. a science book      B. a TV guide       C. a history book
The underlined word "sewage" in the passage means _________.
A. 洗涤               B. 吸尘              C. 排污
According to the passage, the food parts of rubbish can be used to_________.
A. feed animals     B. feed plants     C. clean soil
The passage talks about _________.
A. the need for rubbish collection
B. ways to do with rubbish
C. the process to burn rubbish
How should we take care of a used metal box according to the passage?
A. By burning it off.
B. By putting it in water.
C. By reusing and recycling it.