3. According to the passage, people can live a long life with the help of _______.

A. higher quality of life         B. medical technology C. modern farming machinery       D. technological substitute

(8)

Space travel is definitely bad for astronauts’ bones, reducing their bone density(密度) after only a month of weightlessness, according to French research published on Friday.

Laurence Vico and his fellow workers at St Etienne University called for more research into the effects of microgravity, after their study of 15 astronauts from the Russian MIR station showed bone loss continued throughout space flights.

“Bone loss was especially striking in four astronauts, ” the scientists reported in the Lancet Medical Journal.

They measured the bone mineral density (BMD) of bones in the forearm(前臂) and lower leg of the astronauts who had spent one to six months in space.

The BMD loss was significant in the tibia(胫骨) of the lower leg, a weight-bearing bone, but barely changed in the radius(桡骨) of the forearm. “Our results indicate the need to investigate not only different bones, but also different areas of the same bone since not all sites of the skeleton (骨架) are similarly affected by space conditions, ” they added.

Without gravity the body isn’t bearing any weight so there is no need for calcium (钙) which makes bones strong, and it becomes empty into the bloodstream.

The research team suggested in future scientists should try to determine if the loss of bone density was only on weight-bearing bones on longer flights, also the possible recovery after returning to Earth.

1. What is the main idea of the passage?

A. Water cycle.                  B. Water vapour.

C. How rain forms.         D. Water, vapour, rain. 2. How many ways of the water returning to the air are discussed in the text?

A. Two.           B. Three.  C. Four.    D. Five. 3. Whether water vapour can be seen or not depends on _______. A. how much water is evaporated     B. how good your eyes are

C. in which way water is evaporated       D. climate or weather 4. From the passage we get to know _______. A. there is more water vapour in the air in the tropics than in cold polar regions B. there is more water vapour in the air in cold polar region than in the tropics C. it gets more rain in the tropics than in cold polar regions because there is less vapour D. the amount of water vapour in the air depends on how often it rains

(7)

Technology is the application(应用) of knowledge to production. Thanks to modern technology, we have been able to increase greatly the efficiency of our work force. New machines and new methods have helped cut down time and expense while increasing overall output. This has meant more production and a higher standard of living. For most of us in America, modern technology is thought of as the reason why we can have cars and television sets. However, technology has also increased the amount of food available to us, by means of modern farming machinery and animal breeding techniques, and has extended our life span via(通过) medical technology.

Will mankind continue to live longer and have a higher quality of life? In large measure the answer depends on technology and our ability to use it widely. If we keep making progress as we have over the past fifty years, the answer is definitely yes. The advancement of technology depends upon research and development, and the latest statistics(统计) show that the United States is continuing to pump billions of dollars annually(每年) into such efforts. So while we are running out of some scarce resources(少的资源) we may well find technological substitutes(代用品)for many of them through our research programs.

Therefore, in the final analysis the three major factors of production(land, labor and capital) are all influenced by technology. When we need new skills, on techniques in medicine, people will start developing new technology to meet those needs. As equipment proves to be slow or inefficient, new machines will be invented. Technology responds to our needs in helping us maintain our standard of living.

3. When you want to get cash out in the 21st century, you will _______.

A. need a bank card                  B. have to put in your PIN

   C. move your finger              D. just look directly at the teller machine

(6)

Weather changes when the temperature and the amount of water in the atmosphere change. We can see and feel water coming from the atmosphere when we have rain. But the water must somehow get back to the atmosphere. Meteorologists call this the water cycle.   There are many stages in the water cycle. Rain falls when water vapour in clouds condenses(凝结). Drops of water form and fall to the ground. The water soaks into the ground and feeds streams and rivers. A lot of rain falls into the sea. The heat of the sun evaporates some of the water in the ground and in the rivers, lakes, and the sea. It changes the liquid water into water vapour. The vapour rises onto the air. Water vapour is normally invisible. On a very damp or humid day, however, you can sometimes see water vapour rising from a puddle(水坑) or pond in a mist(薄雾) above the water. Water vapour also gets into the air from living things. Trees and other plants take in water through their roots and give off water vapour from their leaves. People and land animals drink water and breathe out water vapour. In all these ways the water returns to the air. There it gathers to form clouds and condenses to form rain. The rain falls to earth, and the cycle starts again. It continues even if snow or hail(冰雹) fall instead because both eventually melt to form water. The amount of water vapour in the air depends on the temperature. The air is more moist(潮湿) in the tropics(热带) than in the cold polar regions.

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