题目内容
_____ Amy met Peter， she with her mum _______ for the bus at the bus station.
A. When; were waiting B. When; was waiting
C. While; were waiting D. While; was waiting
根据短文意思，从A~F中为每段选择最佳的标题。
A.How it happened like this:few birds， animals or fish in the lake. B.There are many factories around it. C.Polluted water comes into the lake. D.Lake Ponkapog used to be full of life. E.How to save the lake. F.Oil and gas from boats pollute the lake. |
1. Thirty years ago， Lake Ponkapog was full of life. Many birds and animals lived beside the water， which was full of fish. Now there are few birds， animals and fish. The lake water is polluted. It is filled with strange plants.
2. How did this happen? First， we must think about how water gets into Lake Ponkapog. When it rains， water comes into the lake from all around. In the past， there were forests all round Lake Ponkapog， so the rainwater was clean.
3. Now there are many homes around the lake. People often use chemicals in their gardens. They use other chemicals for cleaning or killing insects. There are many factories using chemicals in their machines. When it rains， the rainwater picks up all the chemicals from homes and factories and then carries them into the lake. They pollute the water and kill the animals.
4. Boats on the lake are also a problem. Lake Ponkapog is a popular place for motorboats. But oil and gas（汽油）often get into the lake， so more bad chemicals go into the water in this way.
5. People around the lake love their lake and want to save it. A clean lake must have clean rainwater going into it. Clean rainwater is possible ，only if people are careful about chemicals at home and at work. They must also be more careful about gas and oil and other chemicals on the ground. And they mustn't use motorboats any more on the lake. All these may change people's lives. Only then can Lake Ponkapog be a beautiful clean lake again.
When we found a big fire nearby， we should call 110 for help.