题目内容

  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 have 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.

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 collapse

D. a newly-discovered structure of a molecule

According to the passage,we can 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

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

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 stretched 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

【小题1】C

【小题2】A

【小题3】D

【小题4】B


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Do you want to work with people or animals or machines or tools? Do you want to work indoors or outdoors, directly serve people in need or serve people behind the scenes? These are the typical questions that a volunteer service agency would ask.

   Every year, thousands and thousands of people in the west offer volunteer services. Volunteering greatly strengthens the community partly because it helps the old, the young, the weak, the sick, the disabled and the injured to overcome difficulties.

   Volunteers usually help in many different ways. They may give people advice, offer friendship to the young, drive the elderly to church, counsel kids against drugs. Work as an assistant in a school or nursing home, raise funds, plant trees, help out in local libraries and do many other things.

Volunteering can be a few hours a week or a few hours a month, time during the day, evenings or weekends, either part time or full time. Anybody __________ can become a volunteer.

The art of volunteering is a process of both giving and receiving. Volunteering allows volunteers to meet new people and make new friends and mix with people from all walks of life. Volunteering is an excellent way to experiment, practice and try out new techniques and skills. It is much more effective to practice a skill than to read about it or study it in a classroom. Volunteering is a great way to develop good teamwork skills, discover your individual talents and explore career choices. Being a volunteer takes individuals on a wonderful journey and helps them learn many important things beyond their school.

76. What is the best title of the passage? (Please answer within 10 words)

_______________________________________________________________________77. Which sentence in the passage can be replaced by the following one?

Volunteer service can provide chances for volunteers to make acquaintance of all kinds of people.

_______________________________________________________________________78. Please fill in the blank in the fourth paragraph with proper words, phrases or sentences to complete the sentence. (Please answer within 10 words.)

______________________________________________________________________

79. What kind of volunteer jobs would you like to take? Why? (Please answer within 30 words)

______________________________________________________________________________________________________________________________________________

80. Translate the underlined sentence in the fifth paragraph into Chinese?

____________________________________________________________________________________________________________________________________________

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