Three kids have been learning chemistry for only a few months. But they have already begun to challenge (挑战) a world famous scientist!

   Li Weichi, Huang Runling, and Xiao Yan are from Zhongshan Huaqiao Middle School in Guangdong. They have just found a red cabbage that could be a new kind of acid-base indicator (酸碱指示剂). They want it to take the place of litmus (石蕊) paper.

"We've learnt to think of and ask questions about life by ourselves," said Li, "We work well with each other."

   British scientist Robert Boyle discovered the use of litmus paper over 300 years ago. Now it is used widely in experiments all over the world.

   But when the kids did some experiments in class last winter, they saw that the litmus paper didn’t turn very blue with base matter. It's hard to get a clear result.

  Will there be a better indicator than litmus paper? The three kids decided to try and find out!

    How? They went to collect over 40 plants in parks, gardens and markets. Then they ground (研磨) leaves, flowers and stems (茎) to get the pigments (色素) from them.

   The kids mixed pigments with acid and base. They spent months watching carefully to see which paper showed the best colour change. They decided it was the litmus paper!

"It's our first scientific journey, Huang said, "But it makes me want to try harder."

1. Whom did the three kids want to challenge?

A. Their chemistry teacher.     B. Their headmaster.

C. Robert Boyle              D. Thomas Edison

2. From the text, a red cabbage is a kind of ____.

A. plant　　B. animal　　C. paper　　D. liquid

3.What is widely used as the acid-base indicator now?

A. red cabbage              B. litmus paper

C. any plant                D. any flower 

4.The story mainly tells us ____.

A. how to make litmus paper    B. about the three kids' spirit

C. scientists were wrong        D. the kids are heroes

—Peter, what have done with the poor dog? He is wet through!

—Not ______, mum! I never do the same thing a second time.

A. I 　　　　　　　 B. me　　　　　　　 C. him　　　　 D. he

单词拼写
根据句意及所给首字母完成单词
【小题1】He often takes p　　　in the park.　This is one of them.　It’s beautiful.
【小题2】Mr.Li has got two s　　　and a b　　　.They are clever.
【小题3】We call mother’s sister a　　　and mother’s brother uncle.
【小题4】Your mother’s or father’s mother is your g　　　.
【小题5】He is one of my f　　　.
【小题6】Many parents and g　　　wait outside the school gate when school is over.
【小题7】How many people are there in your f　　　?
【小题8】This is my brother.　H　　　name is Tom.
【小题9】—What is your l　　　name??—Green.
【小题10】Have you got a　　　sisters?