The population of the earth goes on increasing at its present rate and there will eventually not be enough resources left to sustain life on the planet. By the middle of the 21st century, if present trends continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of feeding the human race, the crowded conditions on earth will make it necessary for us to look for open space somewhere else. But none of the other planets in our solar system are capable of supporting life at present. One possible solution to the problem, however, has recently been suggested by an American scientist, Professor Carl Sagan.

Sagan believes that before the earth’s resources are completely exhausted it will be possible to change the atmosphere of Venus（火星）and to create a new world almost as large as earth itself. The difficulty is that Venus is much hotter than the earth and there is only a tiny amount of water there.

Sagan sugges that algae（藻類(lèi)）organisms, which can live in extremely hot or cold atmospheres and at the same time produce oxygen, should be developed in conditions similar to those on Venus. As soon as this has been done, the algae will be placed in small rockets.     Spaceships will then fly to Venus and fire the rockets into the atmosphere. In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.

When the algae have done their work, the atmosphere will become cooler, but before man can set foot on Venus it will be necessary for the oxygen to produce rain. The surface of the planet will still be too hot for men to land on it but the rain will eventually fall and in a few years something like earth will be reproduced on Venus.

1．In the long run, the most difficult problem caused by population growth on earth will probably be the lack of         .

       A．food                   B．oil                       C．space                  D．resources

2．Carl Sagan believes that people might live on Venus because         .

       A．it might be possible to change its atmosphere

       B．its atmosphere is the same as the earth’s

       C．there is a good supply of water on Venus

       D．the days on Venus are long enough

3．Algae can be developed on Venus because they are able to         .

       A．live in very hot temperatures                 B．live in very cold temperatures

       C．produce oxygen                                   D．a(chǎn)ll of the above

4．According to the writer, the most key condition for man to land on Venus eventually is that         .

       A．the algae have done their work              B．the atmosphere becomes cooler

       C．there is enough oxygen                         D．it rains there

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科目：高中英語(yǔ) 來(lái)源： 題型：閱讀理解

America is growing older. Fifty years ago, only 4 out of every 100 people in the United States were 65 or older. Today, 10 out of every 100 Americans are over 65. The aging of the population will affect American society in many ways — edu??cation, medicine, and business. Quietly, the aging of America has made us a very different society — one in which people have a quite different idea of what kind of behavior is suitable at various ages.

A person’s age no longer tells you anything about his/ her social position, marriage or health. There’s no longer a particular year in which one goes to school or goes to work or gets married or starts a family. The social clock that kept us on time and told us when to go to school, get a job, or stop work??ing isn’t as strong as it used to be. It doesn’t surprise us to hear of a 29-year-old university president or a 35-year-old grandmother, or a 70-year-old man who has become a father for the first time. Public ideas are changing.

Many people say, “I am much younger than my mother or my father was at my age.” No one says “Act your age” any more. We’ve stopped looking with surprise at older people who act in youthful ways.

1. It can be learned from the text that the aging of the popula??tion in America ________.

A. has made people feel younger                B. has changed people’s social position

C. has changed people’s understanding of age      D. has slowed down the country’s social development

2. The underlined word “one” refers to ________.

A. a society           B. America          C. a place           D. population

3. “Act your age” means people should ________.

A. be active when they are old              B. do the right thing at the right age

C. show respect to their parents young or old  D. take more physical exercises suitable to their age

4. If a’ 25-year-old man becomes general manager of a big firm, the writer of the text would most probably consider it _________.

A. normal     B. wonderful         C. unbelievable     D. unreasonable

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科目：高中英語(yǔ) 來(lái)源： 題型：閱讀理解

America is growing older. Fifty years ago, only 4 out of every 100 people in the United States were 65 or older. Today, 10 out of every 100 Americans are over 65. The aging of the population will affect American society in many　ways — edu??cation, medicine, and business. Quietly, the aging of America has made us a very different society — one in which people have a quite different idea of what kind of behavior is suitable at various ages.

A person’s age no longer tells you anything about his/ her social position, marriage or health. There’s no longer a particular year in which one goes to school or goes to work or gets married or starts a family. The social clock that kept us on time and told us when to go to school, get a job, or stop work??ing isn’t as strong as it used to be. It doesn’t surprise us to hear of a 29-year-old university president or a 35-year-old grandmother, or a 70-year-old man who has become a father for the first time. Public ideas are changing.

Many people say, “I am much younger than my mother or my father was at my age.” No one says “Act your age” any more. We’ve stopped looking with surprise at older people who act in youthful ways.

It can be learned from the text that the aging of the popula??tion in America ________.

A. has made people feel younger

       B. has changed people’s social position

C. has changed people’s understanding of age

D. has slowed down the country’s social development

The underlined word “one” refers to ________.

A. a society           B. America          C. a place           D. population

“Act your age” means people should ________.

A. be active when they are old

B. do the right thing at the right age

C. show respect to their parents young or old

D. take more physical exercises suitable to their age

f a’ 25-year-old man becomes general manager of a big firm, the writer of the text would most probably consider it _________.

A. normal      B. wonderful         C. unbelievable     D. unreasonable

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源： 題型：閱讀理解

America is growing older. Fifty years ago, only 4 out of every 100 people in the United States were 65 or older. Today, 10 out of every 100 Americans are over 65. The aging of the population will affect American society in many ways — edu?cation, medicine, and business. Quietly, the aging of America has made us a very different society — one in which people have a quite different idea of what kind of behavior is suitable at various ages.
A person’s age no longer tells you anything about his/ her social position, marriage or health. There’s no longer a particular year in which one goes to school or goes to work or gets married or starts a family. The social clock that kept us on time and told us when to go to school, get a job, or stop work?ing isn’t as strong as it used to be. It doesn’t surprise us to hear of a 29-year-old university president or a 35-year-old grandmother, or a 70-year-old man who has become a father for the first time. Public ideas are changing.
Many people say, “I am much younger than my mother or my father was at my age.” No one says “Act your age” any more. We’ve stopped looking with surprise at older people who act in youthful ways.

  1. 1.

    It can be learned from the text that the aging of the popula?tion in America ________.

    1. A.
      has made people feel younger
    2. B.
      has changed people’s social position
    3. C.
      has changed people’s understanding of age
    4. D.
      has slowed down the country’s social development
  2. 2.

    The underlined word “one” refers to ________.

    1. A.
      a society
    2. B.
      America
    3. C.
      a place
    4. D.
      population
  3. 3.

    “Act your age” means people should ________.

    1. A.
      be active when they are old
    2. B.
      do the right thing at the right age
    3. C.
      show respect to their parents young or old
    4. D.
      take more physical exercises suitable to their age
  4. 4.

    f a’ 25-year-old man becomes general manager of a big firm, the writer of the text would most probably consider it _________.

    1. A.
      normal
    2. B.
      wonderful
    3. C.
      unbelievable
    4. D.
      unreasonable

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