Each year, road accidents kill a million people and injure millions more . The economic costs are greatest for developing countries . Earlier this year , the United Nations called for a campaign to improve road safety .
One way to avoid accidents is better driving . Another is better roads and bridges . Engineers in the Unites States have designed ten new concrete mixtures that they think could make bridges last longer .
Professor Paul Tikalsky leads the experiments by a team at Pennsylvania State University . He says bridges made of concrete now last about twenty-five to thirty-five years . But he says the new mixtures might extend that to seventy –five or even one-hundred years .
Concrete is made of stone , sand , water and cement(水泥). The materials in the cement hold the concrete together . Ancient Romans built with concrete . Yet strengthened concrete bridges did not appear until the late 1800s . People keep looking for new ways to improve concrete . Professor Tikalsky says it is one of the most complex of all chemical systems .
The new mixtures designed by his team contain industrial waste products . He says these make the concrete better able to resist damage from water and salt over time . One of the products is fly ash . This is released into the air as pollution when coal is burned .
Professor Tikalsky says particles (颗粒)of fly ash are almost exactly the same size and chemical structure as Portland cement . This is the most costly material in concrete . So using fly ash to replace some of it would save money .
The federal government is paying for part of the research . Engineers anywhere can use the technology . Professor Tikalsky says some of the ideas have already been put to use in China , the Philippines and other countries .
1.Why did the United Nations launch the campaign ?
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A．Because the United Nations wanted to reduce road accidents and economic costs |
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B．Because two million people were killed in the accidents . |
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C．Because engineers wanted to design ten new concrete mixtures . |
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D．Because the United Nations made bridges of the new mixtures which could last for about 20 to 35 |
years .
2.What does the underlined word “ this ” in the sixth paragraph refer to ?
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A．Fly ash |
B．Portland cement |
C．Sand |
D．Chemical |
3.Which of the following statements is TRUE ?
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A．Ten new concrete bridges have already been built in the United States . |
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B．A new concrete bridge could last 50 more years than an ordinary concrete one . |
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C．People didn’t know how to build with cement until the late 1800s . |
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D．Water and salt won’t do any damage to bridges over time . |
4.What does the passage mainly tell us ?
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A．The causes of road accidents . |
B．The advantages of fly ash |
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C．The measures of avoiding road accidents |
D．Latest information about long-life concrete bridges |
完型填空（共20小题；每小题1.5分，满分30分）
阅读下面短文，掌握其大意，然后从36—55各题所给的四个选项（A、B、C和D）中，选出最佳选项，并在答题卡上将该项涂黑。
We always celebrated Dad’s birthday on Thanksgiving Day, even after he entered a nursing home . As years went on , these events took on a 36 meaning for me : A traditional birthday party for Dad , and thanking for all that he had been doing to me in my life . When we knew it might be his 37 birthday, the whole family decided to 38 together for a huge birthday celebration at the nursing home .
Dad was a good story-teller and here was the 39 he had had .During a quiet moment , I announced it was now Dad’s 40 to listen to stories for a change . I wanted everyone to tell Dad what we loved about him . The room became 41 . Then one after another , people told stories from their hearts , while Dad 42 with tears in eyes . People 43 kinds of stories — stories about when they were little , stories about when Dad was young , and stories that shared family treasures .
The stories 44 . Everyone seemed to have more than one story . Even the little grandchildren couldn’t 45 to tell Dad why they loved him . For a man who had been kind to so many people in his life , here was our 46 to celebrate him . A few months later , at Dad’s memorial service , we more fully realized what we had 47 Dad that night . Those are the stories people 48 tell at a funeral (葬礼)after a loved one is no longer 49 to hear the words . They tell stories , full of 50 . But we had given those memories to Dad in his 51 , and we had told them through laughter , accompanied by hugs and joys . He had them to 52 and roll over in his mind during his last days and months .
Words do 53 , and they are enough . We just need to say them or to speak them 54 to the ones we love . That’s the way to 55 love and our chance to celebrate a person in his or her life .
36. A. special B. valuable C. double D. complex
37. A. another B. last C. important D. fiftieth
38. A. unite B. arrange C. move D. gather
39. A. career B. pride C. happiness D. audience
40. A. choice B. wish C. turn D. right
41. A. lively B. still C. cosy(舒适的) D. noisy
42. A. thought B. nodded C. listened D. accepted
43. A. understood B. invented C. recalled D. discussed
44. A. flowed B. passed C. unfolded D. differed
45. A. stop B. stand C. afford D. wait
46. A. responsibility B. situation C. chance D. desire
47. A. returned B. left C. given D. owed
48. A. sincerely B. gently C. normally D. regularly
49. A. available B. happy C. eager D. alive
50. A. tears B. feelings C. joy D. peace
51. A. mind B. life C. world D. work
52. A. hold B. share C. consider D. continue
53. A. suit B. fail C. survive D. matter
54. A. willingly B. publicly C. actually D. truly
55. A. get back B. call up C. give back D. keep up
It’s such a good place ______ everybody wants to visit _____ it is well known all over the world .
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A．which , that |
B．as , as |
C．as, that |
D．that , which |
On the man’s face , there was a smile that seemed to suggest that he _______ in suggesting that the meeting ______ off .
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A．should succeed , was put |
B．succeeded , put |
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C．should succeed, be put |
D．succeeded , be put |
After a heated discussion , an agreement _____ and the meeting ________ .
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A．reached , came to an end |
B．was reached , put an end to |
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C．arrived at , bring to an end |
D．was arrived at , came to an end |
You may borrow my bike ______ you can return it on time .
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A．while |
B．even if |
C．unless |
D．on condition that |
