摘要: collect water 挑水 16. write original songs 写原创歌曲 17. make a music video 制作音乐录影带

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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 color 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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It was a cold day, but the students from Prosser Middle School in Chicago were sorting through the waste when they found that their school produces 1,500 pounds every day.
Prosser is just one school that throws out nearly 4,000 meal trays every day. Counting all of Chicago’s public schools, the number comes to nearly a quarter of a million a day. That’s more than 1 million a week and about 5 million a month.
“None of the trays are being recycled,” said a teacher. “ Everyone agrees that it’s very bad.”
Luckily, concerns about the environment and health have made some US cities take action. Dozens of schools have begun programs to reduce the use of food trays in school.
These schools have also banned (禁止)some fast food, including McDonald’s. Instead, they offer students recyclable trays. They encourage students to sort out lunchroom waste, then wash and recycle milk cartons and trays . So far, the program has helped schools to save a total of 820,000 trays each week.
Jay Stream Middle School in Illinois teaches its students how to collect trays. The school has cut its lunchroom waste by two thirds now that students recycle their used trays instead of breaking them.
Prosser Middle School also sees the benefits of the program. Students have organized about 20 clubs and volunteer activities to cut down on cafeteria garbage. They now recycle 80 percent of the school waste. “ I joined the club,” said Erika Santana, a 16-year-old junior in Prosser, “because I want to make Earth a better place.”

【小题1】Did Prosser Middle School create much garbage every day before the program ?
【小题2】How many meal trays do public schools in Chicago throw out a day?
【小题3】What does Jay Stream Middle School teach its students to do?
【小题4】Who joined the club?
【小题5】What’s the passage about ?

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用方框中所给单词的适当形式填空,使短文通顺、正确、连贯(每个单词限用一次)

 

time  horse  by  also  enough  however  few  ready  send  hold

 

 

 

To: Christin foo@hotmail.com

Date: 23rd March

Subject: The Riding for the Disabled Association

Hi Christine,

Sorry I haven’t emailed lately —I’ve been very busy since becoming a volunteer for the Riding for the Disabled Association.

Every Saturday, I help to get the horses 1.___________ for the disabled(残疾) riders. Many more disabled people want to ride 2.___________ than you’d imagine. It’s a disadvantage that I don’t know how to ride —I’d love to got on long rides with the riders— but I’ll learn soon 3.___________. Right now, I’m just happy to be able to lead the horses around for the disabled riders.

I’m4.___________ helping to organize a sale, which will be 5.___________ next month. It’s a lot more work than helping the disabled. I need to collect second-hand things to sell at the sale. There are 6.___________ things available(获得的) than I thought, but I’m sure we’ll have enough7.__________ next month.

I hope the sale raises more money than last month’s walk. It was rainy, so too few people took part in the event. Last week, we held an auction(拍卖). The auction took much less 8.__________ to organize than the walk. 9.__________, for some reason, people offered too little money for the things, so we didn’t raise enough money.

I’m 10.___________ you some pictures in the letter, as well as a speech I gave last week.

 

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