一Will there be more people in l00 years，do you think?

一        ，I hope．

A．No，there isn’t             B．No，there aren’t

C．No，there won’t            D．No，they won’t

Will there be any paper money ________ 100 years?

Tom and Fred were talking about the year 2050.
　　“What will   36  be like in the year 2050?” asked Tom.
　　“I don’t know,” said Fred. “What do you think?”
　　“Well, no one knows. But it is __37__ to guess,” said Tom. “In the year 2050 everybody will carry a pocket (袖珍) __38___. The computer will give people the __39__ to all their problems. We shall all have telephones in our pockets,__40___ . And we’ll be able to talk to our friends all over the world. Perhaps(也许) we’ll be able to ___41__ them at the same time. Machines will do ___42___of the work, and people will have more__43___. Perhaps they will work only two or three days a week. They will be able to fly to the moon by spaceship and spend their holidays there.”
　　“I’m very _44__to hear that. I hope to fly to the moon. And I hope I’ll be able to live _45___,” said Fred. “Won’t that be interesting? Just like a fish.”

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

Will there be any paper money ________ 100 years?