Three kids have been learning chemistry for only a few months. But they have already begun to challenge (挑戰(zhàn)) 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 (酸堿指示劑). 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 (莖) 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."
小題1: Whom did the three kids want to challenge?
A．Their chemistry teacher.B．Their headmaster.
C．Robert BoyleD．Thomas Edison
小題2: From the text, a red cabbage is a kind of ____.
A．plantB．a(chǎn)nimalC．paperD．liquid
小題3:What is widely used as the acid-base indicator now?
A．red cabbageB．litmus paper
C．a(chǎn)ny plantD．a(chǎn)ny flower
小題4:The story mainly tells us ____.
A．how to make litmus paperB．a(chǎn)bout the three kids’ spirit
C．scientists were wrongD．the kids are heroes

小題1:C
小題1:A
小題1:B
小題1:B

本文講的是三個中學(xué)生入挑戰(zhàn)世界聞名的科學(xué)家Robert Boyle使用石蕊紙的事，告訴我們做事要有一種堅持的精神。
1. C 答案來自于本句：British scientist Robert Boyle discovered the use of litmus paper over 300 years ago，屬于對細(xì)節(jié)的理解，選C，其它幾項未說到。
2. A 此題屬于推理題，要聯(lián)系上下文才能找到答案。從下文They went to collect over 40 plants in parks, gardens and markets可知是一種植物plant,故選A。
3. B 對細(xì)節(jié)題的考查。在Now it is used widely in experiments all over the world中的it指代的就是上方說到的litmus paper，故正確答案為B。
4. B 本題是個歸納總結(jié)題。文章從他們?nèi)齻�決定挑戰(zhàn)到后面努力收集尋求的過程，說明他們?nèi)齻�的精神的可貴，這也是這篇文章的主旨所在，選B。
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科目：初中英語 來源：不詳 題型：閱讀理解


What does a UFO look like? Do you believe there are aliens outside the earth? Maybe nobody can tell us exactly, but some of us believe that we humans are not alone in this world. We have friends living outside the earth. And a lot of people in the world think they really have seen a UFO flying in the sky. Now many scientists are trying to understand the origin of the UFO sightings. Scientists even try to draw pictures about aliens and aliens’ life according to their imagination.        
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Answer the questions（根據(jù)短文內(nèi)容回答下列問題)
Your Nose is Busy and Important
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●Reducing loss of   50.
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A．hardB．interestingC．easyD．exciting
小題2:
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小題3:
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