Things similar continuously happened in Haiti and Chile．Thousands of people were
buried in the earthquake and lost their fives．What if we could have warned them? People are always trying hard to find a way of preventing building collapsing(坍塌)．Better materials and technology help，but are not a solution．Just like humans，a building has its own life circle from “birth” to “death”．If we know when a building is going to collapse，we can repair it in advance or get out before it falls．
Now, scientists at the University of Illinois ha、，e developed a material that turns red before it breaks．The invention could be used in things like climbing ropes，or bridge supports．The secret behind the color-changing material is a type of molecule(分子)．A molecule is a group of atoms held together by chemical bonds(化学键)．Imagine you and your friends standing in a circle，holding hands．Each person stands for one atom，your hands represent the bonds，and the entire circle represents a molecule．If one person lets go of his or her hands，the molecule changes color．The research team put the molecule into a soft material．When the researchers stretched(拉长) the material：it turned bright red a few seconds before it broke into two pieces．
When they repeatedly stretched and relaxed the material，without breaking it，it only turned a little red．
The major problem is，light can get rid of the red color．When the team shone a bright light on the molecule，the broken bond was fixed，and the color disappeared．If bright fight keeps the red color from appearing，the material’s warning system will be useless．Scientists still have a lot of work to do before the color-changing molecule can be used outside the lab．
49. The passage mainly about
A. a way of preventing building from breaking down
B. a series of earthquakes in Haiti and Chile
C. a way of warning before buildings collage
D. a newly-discovered structure of a molecule
50．According to the passage，we call conclude that
A．there are problems to solve before putting the new material to use
B．scientists have found the life circle of buildings from “birth” to “death”
C．bright fight makes the red color visible to human eyes
D．the new material is unlikely to be used in building bridges
51．The color-changing molecule can
A．make building materials much stronger
B．help building materials get stretched if necessary
C．prevent the earthquake from killing people
D．remind people to leave buildings before they fall
52．The warning system is based on the fact that
A．red color won’t show up when it meets bright fight
B．a material with a certain type of molecule Can turn red when s廿etched
C．a building has its own life circle of “birth”to“death”
D．the broken bond will fix itself when a molecule meets bright fight
文敬图书课时先锋系列答案科目：高中英语 来源： 题型：阅读理解
Directions: Complete the following passage by using the words in the box. Each word can only be used once. Note that there is one word more than you need.
| A. recently B. forming C. locate D. primitive E. fascinated F. evidence G. volcanic H. chemicals I. created J. closely |
Since early times, people have been ___41___with the idea of life existing somewhere else besides earth. Until recently, scientists believe that life on other planets was just a hopeful dream. But now they are beginning to___42____places where life could form. In 1997, they saw ____43____of planets near other stars like the sun. But scientists now think that life could be even nearer in our own solar system. One place scientists are studying very closely is Europa, a moon of Jupiter. Space probes(探测器) have provided evidence that Europa has a large ocean under its surface. The probes have also made scientists think that under its surface Europa has a rocky core（核心） giving off____44____heat. Water and heat from volcanic activity are two basic conditions needed for life to form. A third is certain basic____45____such as carbon, oxygen and nitrogen. Scientists believe there might be such chemicals lying at the bottom of Europa’s ocean. They may have already____46____life or may be about to. You may wonder if light is also needed for life to form. Until____47____, scientists thought that light was essential. But now, places have been found on earth that are in total blackness such as caves several miles beneath the surface. And bacteria,___48____ forms of life, have been seen there. So the lack of light in Europa’s sub-surface ocean doesn’t automatically rule out life____49____.
查看答案和解析>>
科目：高中英语 来源： 题型：阅读理解
SECTION B
Directions: For each blank in the following passage there are four words or phrases marked A, B, C, and D. Fill in each blank with the word or phrase that best fits the context.
It was early spring. The sun was strong and warm. I went over the hillside fields behind my village, 36 buntings and linnets, the birds I loved most.
I turned along a bush between two fields where I had seen the birds before, but on this fine day almost the first birds that I saw were winter visitors. I was 37 not to see a bunting straightaway, but I went on, stopping occasionally to look at the black-thorn (黑刺李) flowers in the bush, and 38 I did hear a bunting singing. Or was it? Was I not perhaps turning a note of skylark (云雀) song into that of the song I was hoping to hear?
But the bunting’s song was pretty clear, and within a few minutes I was proved
39 . The song was coming from the bush, and as I approached 40 I saw the brown bird resting in a small tree. It opened its mouth, and 41 once more. Then it flew off. It was the only one I saw that day, but at least I had found one of the birds I had 42 .
It was not until I was on my way back home that I caught sight of some 43 . I saw five of them gathering on the ground when I was just coming back beside the
44 where I had found the bunting. As I came nearer, they flew up, spreading their tails so that their white edges 45 to look like a white fan in the sky. Then, to my
46 , some big pigeons suddenly came flying and joined the linnets. A moment later they had all 47 but I had fulfilled my hopes for the day.
36.A. looking at B. looking for C. looking up D. looking after
37.A. disappointed B. dismissed C. dissatisfied D. disturbed
38.A. directly B. gradually C. suddenly D. immediately
39.A. proper B. right C. useful D. true
40.A. sadly B. hurriedly C. proudly D. quietly
41.A. danced B. ate C. sang D. shouted
42.A. observed B. noticed C. expected D. described
43.A. linnets B. skylarks C. pigeons D. buntings
44.A. bush B. road C. grass D. black-thorn
45.A. widened B. enlarged C. lengthened D. expanded
46.A. knowledge B. pleasure C. amusement D. honour
47.A. gathered B. lost C. missed D. gone
查看答案和解析>>
科目：高中英语 来源： 题型：
Since many young people have become rich on Taobao.com, I wonder what ____is like to run a successful on – line business.
A．this B．that C．it D．one
查看答案和解析>>
科目：高中英语 来源： 题型：
The road ______ for vehicles is under repair. Drivers are required to take some other routes.
A. meaning B. meant C. to mean D. being meant
查看答案和解析>>
科目：高中英语 来源： 题型：
My friend Paul was badly cheated when he paid $1000 for that second-hand car; it was not worth _____.
A. that all much B. all that much C. that much all D. much all that
查看答案和解析>>
科目：高中英语 来源： 题型：
The train ______ at seven o’clock and you’d better get to the station by half past six.
A. due to start B. is due to start C. is due to starting D. owe to start
查看答案和解析>>
科目：高中英语 来源： 题型：
27. ________ of the ________ life in the city, Mr Blaster, with his wife and daughter, moved to the countryside.
A. Tiring; boring B. Tired; bored C. Tiring; bored D. Tired, boring
查看答案和解析>>
科目：高中英语 来源： 题型：
102 _______ is our belief that improvements in health care will lead to a stronger, more prosperous economy.
A. As B. That C. This D. It
查看答案和解析>>
湖北省互联网违法和不良信息举报平台 | 网上有害信息举报专区 | 电信诈骗举报专区 | 涉历史虚无主义有害信息举报专区 | 涉企侵权举报专区
违法和不良信息举报电话：027-86699610 举报邮箱：58377363@163.com
