A Simple Scientific Experiment
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Below is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water. Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water. Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner. |
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Iron in dry air Method (1) Put some iron nails at the bottom of a test tube. (2) Push some cotton wool down the tube. (3) Leave the tube for one week. Result After one week, the nails have not rusted. Conclusion Iron does not rust in dry air. Iron in air-free water Method (1) Half-fill a test tube with water. (2) Boil the water for three minutes. (This makes sure there is no air in the water. (3) Put two or three clean nails in the water. |
(4)Add some oil to the water. (This will keep air out of the water.) (5) Leave the tube for one week. Result The nails do not rust in the tube with air-free water. Conclusion Iron does not rust in air- free water. Iron in ordinary water Method (1) Half –fill a test tube with water and add two or three clean nails. (2) Leave the tube for one week. Result The nails rust in the tube with ordinary water. Conclusion Iron rusts in ordinary water. (238 words) |
1.In the first part of the experiment the cotton wool is most probably used to ______________.
A. keep the air dry B. keep the tube wet
C. make the nails rust D. keep the tube clean
2.What are necessary steps to make sure the water in the tube is air free?
①Leave half a tube of water in it
②Boil the water for some time
③Put some clean iron nails in the tube
④Add some oil to the water
A. ①② B. ①③ C. ②③ D. ②④
3.We can conclude from the experiment that only ____________ makes iron rusty.
A. dry air B. cotton wool C. ordinary water D. air-free water
从方框中选择恰当的词或短语并用其正确的形式填空。
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be absent ; try one’s best ; excite ; provide … with ; deal with ; rob …of ; pay attention to ; from time to time ; get off ; polite |
1.The audience clapped and shouted with ___________________ when the performer appeared.
2.You’d not __________________ before the bus stops. Otherwise you may be hurt.
3.These days we _____________________________________ to get good marks in the exams.
4.My friends and I go to museums ________________________ to learn what we can’t get from textbooks.
5.I helped Susan with her lessons, for she ___________________ from school for a week.
6.UNICEF ______________________ poor kids in developing countries ___________ better education.
7.It’s __________________ for the young to argue with the elderly.
8.If you want to improve your spoken English, you should _________________________ your pronunciation.
9.The lady ________________by a young man ________ her handbag while she was walking alone.
10.Don’t do everything for teenagers. They are wise enough ________________________ their own problems.
请认真阅读下面短文,在短文后表格中的空白处填入适当的单词(注意:每空1个单词)。
CCTV cameras watch action
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In UK , Closed Circuit Television (CCTV) cameras are everywhere. They help the police solve crimes and keep the streets safe. But that’s not all they do . They also catch people doing very stupid or smart things.
One of the videos is of a British woman Mary Bale. She clearly doesn’t like cats. In 2010 she was caught on CCTV throwing one into a dustbin. The video shows Mary walking down a quiet street. All of sudden , she notices Lola the cat jump onto a fence. Mary stops to pickup Lola and drops her into a large dustbin . Lola was saved fifteen hours later. And Mary was arrested for causing unnecessary suffering to an animal . She was fined ( 罚款)£250 and was not allowed to own pets for five years.
Another video shows “ Britain’s drunkest man” . He’s been at a party at London’s Savoy Hotel. And he’d obviously had a few too many glasses of beer. At about 2 a. m. , he was kicked out for being too drunk . So, he decided to walk home. On the way , CCTV cameras filmed him falling down stairs and crossing the roads madly… A Savoy Hotel waiter said, “ It’s amazing he didn’t hurt himself badly.”
Sometimes they also record smart events. Once a British band The Get Out Clause didn’t have any money to make a music video. So , they came up with an unbelievable idea. They set up their instruments ( 乐器) and played a song in front of eight CCTV cameras. And then, according to the English Freedom of Information Act , they asked for a copy of all the footages ( 视频) , which they edited. The result is that a totally new music video was made, and it didn’t cost them a penny.
Title: CCTV cameras catch action
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Passage outline |
Supporting details |
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Usage of CCTV cameras |
They are almost (1)______________ and are used in many ways. |
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To help the police solve crimes |
A woman saw a lonely cat and (2) ___________ it into a big dustbin. She was fined £250 and was not allowed to own pets for five years. |
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To catch people doing stupid things |
A man got very drunk and was thrown out of London’s Savoy Hotel. He went back home through a lot of troubles and dangers but was not (3) ________________hurt. |
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To (4)____________ people doing Smart events |
A band had no money but still wanted to make a music record. They played in front of eight CCTV cameras and asked for the footage copy for (5) ___________________. They edited the footages and make a totally new music video. |