题目内容：

The population of the Earth is growing faster. It is important that we look after the Earth. We need it!

The Earth gives us a lot of things. We also give the Earth a lot, but some of the things are not good.

In nature, when something dies, other animals and plants get food from it. Every animal or plant gives food for other animals or plants. However, animals can't get food from many of the things that we “give” the Earth. Animals and plants can't eat metal, plastic and glass. These things will stay in the ground for many, many years.

Some rubbish is very dangerous for plants and animals. In some places, many animals live together. One animal makes food for many more animals. If we put rubbish and chemicals (化学制品) in the water, the plankton(浮游生物) can die. If there isn't any plankton, many animals have nothing to eat.

So what can we do? Don't leave any rubbish in the countryside! Don't make so much rubbish!

1.When something dies in nature, _________.

A.water and grass are polluted B.plastic and wood become food

C.other animals and plants get food D.metal and glass stay in the ground

2.Many animals live together in some places to _________.

A.clean the rubbish and chemicals B.provide food to each other

C.eat the plankton D.get warm from each other

3.We must __________to look after the Earth.

A.put metal in the ground B.use more wood

C.keep frogs in the water D.make less rubbish