摘要:( ) A. colour B. classmate C.mom D. umbrella

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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

 

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Hello. I’m a boy. I’m Tony Smith. I’m thirteen years old. I’m in Class 2, not Class 3. My telephone number is seven five six, six two three one. I like summer best because(因为) I can go swimming in summer. This is my friend, Betty, Betty White. She is American. We are in the same(相同的) class. Her telephone number is two two four, five six one seven. She likes dogs very much. She has 3 white dogs and 2 black dogs. Our English teacher is Miss Li. Her telephone number is six eight one, four five two seven. Her favourite colour is green and she likes drawing.

1.What’s the boy’s name?

A. Tony White           B. Tony Smith              C. Betty White         D. Betty Smith

2.Betty has _________ dogs.

A. one                                 B. two                                  C. three                      D. five

3.What class is Betty in?

A. Class 1                  B. Class 2                             C. Class 3                     D. Class 4

4.What’s Miss Li’s favourite colour?

A. red                                   B. yellow                     C. white                      D. green

5.What’s Miss Li’s number?

A. 756-6213            B. 671-4527            C. 681-4527         D. 224-5617

 

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Many scientists find that colours can change people’s feelings. It’s very interesting. Some colours can make people feel relaxed,and some colours can make people feel nervous. Now,this kind of knowledge is being used in many places. For example, school walls are always painted green because green makes students feel relaxed. It is also good for the students’ eyes. Some books are also green or light blue for the same reason. Restaurant owners not only have to know how to make food,but also have to know how to make money. Here are some things they’ve learned from scientific studies. The colour red makes people hungry. Many fast food restaurants have red furniture or walls. Soft colours like pink and light blue make people feel relaxed,so they spend more time eating. Loud music may be nice at first,but it soon makes people want to leave. Hard seats also make customers want to eat quickly and leave. Many restaurants,especially fast food restaurants,use this knowledge to make customers eat faster.

1.How does the colour green make the students feel?

A. Hungry.                                      B.Nervous.                           C.Angry.                       D.Relaxed.

2.How does the colour red make most people feel?

A.Hungry.                             B.Comfortable.           C.Excited.           D.Worried.

3.Which colour isn’t mentioned in this passage?

A.Green.                               B.White.                                C.Light blue.               D.Red.

4.What do many fast food restaurants do?

①Play loud music.  ②Play soft music.  ③Have hard seats.  ④Paint their walls red.

A.①②③                              B.①③④                              C.①②④                     D.②③④

5.What’s the best title for this passage?

A.Colour and restaurant.

B.Use colour to make money.

C.Colour and science.

 D.Use colour to change feelings.

 

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