There are three separate sources of danger in supplying energy by nuclear power(原子能).

First, the radioactive material must travel from its place of production to the power station. Although the power stations themselves are strongly built, the containers used for the transport of the materials are not. Normally, only two methods of transport are in use, namely road or rail. Unfortunately, both of these may have an effect on the general public, since they are sure to pass near, or even through, heavily populated areas.

Second, there is the problem of waste. All nuclear power stations produce wastes that in most cases will remain radioactive for thousands of years. It is impossible to make these wastes nonradioactive, and so they must be stored in one of the inconvenient ways that scientists have invented. For example, they may be buried under the ground, or dropped into deserted mines, or sunk in the sea. However, these methods do not solve the problem, since an earthquake could easily break the containers.

Third, there may occur the danger of a leak(泄漏) or an explosion at the power station. As with the other two dangers, this is not very likely, so it does not provide a serious objection to the nuclear program. However, it can happen.Separately, these three types of dangers are not a great cause for worry. Taken together, though, the probability of disaster(灾难) is extremely high.

1.Which of the following is FALSE?

A.It is possible that a leak or an explosion occurs at a power station.

B.It is unusual for radioactive materials to be transported across land.

C.The containers are likely to be broken by an earthquake.

D.Nuclear wastes remain dangerous in most cases for many years. 

2.The author thinks that the ways to store nuclear wastes are ________.

A.easy      B.impossible         C.reasonable        D.ineffective 

3.What do we learn from the last paragraph?

A.The power station is a safe place.

B.The dangers of nuclear energy can be prevented.

C.The general public are strongly against the nuclear program.

By itself, none of the three dangers is very likely to cause much worry.

4.What is this passage about?

A.Uses of nuclear power.          B.Dangers from nuclear power.        

C.Public anger at nuclear power.  D.Accidents caused by nuclear power. 

    To swim across the English Channel takes at least nine hours. It‘s hard work and it makes you short of breath. To fly over the channel takes only twenty minutes as long as you’re not held up at the airport， but it‘s an expensive way to travel. You can travel by hovercraft （气垫船）if you don’t mind the noise and that takes forty minutes. Otherwise， you can go by boat， if you remember your sea-sickness pills. All these means of transport have their problems， and the weary（厌烦的）traveler often dreams of being able to drive to France in his own car. “Not possible， you say. Well， wait a minute. People are once again considering the idea of a channel tunnel or bridge.” This time， the great London Council（议会）is looking into the possibility of building a channel link straight to London. A bridge would cost far more than a tunnel， but you would be able to by rail or by car on a bridge， yet a tunnel would provide a rail link only. Why is this idea being discussed again？ Is Britain realizing the need for links with Europe as a result of joining EEC？ Well， perhaps， the main reason， though， is that a tunnel or bridge would reach the twenty square kilometers of London‘s discussed dockland（船坞）。 A link from London to the continent would stimulate（刺激） trade and revitalize（使重新具有活力）the port， and would make London a main trading center in Europe. With a link over the Channel， you could buy your fish and chips in England and be able to eat them in France while they are still warm！

From the lines we can see that people crossed the Channel by ______ in the past.

    A. air          B. boat        C. Swimming          D. A， B， or C

The weary traveler thinks the best way to cross the Channel is ______.

    A. by swimming      B. in his own car     C. by air        D. by hovercraft

A tunnel would cost______ a bridge.

    A. far less than     B. as much as    C. far more than    D. as little as

According to the passage， a link from London to the continent would be______.

    A. necessary for its trade          B. important for its politics

    C. useful for its industry          D. helpful for its culture

The main idea of the passage is______.

A. how to develop the trade of London     

B. when to cross the Channel

C. how to get to Europe from London more conveniently

D. what to do in the developing of traveling

Man is a land animal, but he is also closely tied to the sea. Throughout history the sea has served the needs of man. The sea has provided man with food and a convenient way to travel to many parts of the world. Today, nearly two—thirds of the world’s population live within 80 kilometers of the sea coast.
In the modern technological world, the sea offers many resources to help mankind survive. Resources on land are beginning to be used up. The sea, however, still can be hoped to supply many of man’s needs.
The list of riches of the sea yet to be developed by man’s technology is immense. Oil and gas explorations have been carried out for nearly 30 years. Valuable amounts of minerals exist on the ocean floor ready to be mined.
Fish farming promises to be a good way to produce large quantities of food. The culture of fish and shellfish (贝类动物) is an ancient skill practised in the past mainly by Oriental people.
Besides oil and gas, the sea may offer new sources of energy. Experts believe that the warm temperature of the ocean can be used in a way similar to the steam in a steamship. Ocean currents and waves offer possible use as a source of energy.
Technology is enabling man to explore ever more deeply under the sea. The development of strong, new materials has made this possible.
The technology to harvest the sea continues to improve. Experts believe that by the year 2020 the problems that prevent us from exploiting fully the food, minerals, and energy sources of the sea will be largely solved.
1. The major things that the sea offers man are ______.
A. fish and oil                           B. minerals and oil
C. warm temperature and ocean currents       D. the food, energy sources, and minerals
2. The sea serves the needs of man because ______.
A. in provides man with food              B. it offers oil to man
C. it supplies man with minerals            D. all of the above
3. We can conclude from this passage that ______.
A. the sea resources have largely been used up
B. the sea, in the broad sense, has not yet been developed
C. the problems that prevent us from using the food, minerals, and energy sources of the
sea have already been solved.
D. by the year 2000 , the technology will be good enough to exploit all the sea resources
4. The underlined words Oriental people in the fourth paragraph probably mean ______.
A. the people in Asia                  B. African people
C. European people                   D. American people
5. The best title for this passage is ______.
A. Sea Harvest                       B. Sea Food
C. Technology for Exploiting the Sea     D. Man and the Sea

WASHINGTON—Two-thirds of the world’s polar bear population could be gone by 2050 if predictions of melting sea ice hold true, the US Geological Survey reported on Friday.

The fate of polar bears could be even worse than that estimate, because sea ice in the Arctic might be disappearing faster than the available computer models predict, the geological survey said in a report aimed at determining whether the big white bear should be listed as a threatened species.

“There is a definite link between changes in the sea ice and the welfare of polar bears,” said Steve Amstrup, who led the research team. He says Arctic sea ice is already at the lowest this year and is expected to retreat(退却) farther this month.

That means that polar bears—some 16,000 of them -- will disappear by 2050 from parts of the Arctic where sea ice is melting most rapidly, along the north coasts of Alaska and Russia, researchers said in a telephone briefing(简报).

Other polar bears could survive beyond that date but many of those could be gone by 2100, Amstrup said. By this century’s end, the only polar bears left might live in the Canadian Arctic islands and along the west coast of Greenland.

“It is likely to result in loss of approximately two-thirds of the world’s current polar bear population by the mid 21st century,” the report’s executive summary said.

“Because the observed trajectory(轨迹)of Arctic sea ice decline appears to be underestimated by currently available models, this assessment of future polar bear status may be conservative(保守的).”

In January, the US Fish and Wildlife Service proposed listing the polar bear as a threatened species, noting polar bears depend on sea ice as a platform to hunt seals, their main food.

Without enough sea ice, polar bears would be forced onto land, but they are poor hunters once they get out of the water and ice, the researchers said. The bears’ disappearance would probably take place as young cubs(幼兽)failed to survive to adulthood and females were unable to reproduce successfully.

1.What was the US Geological Survey intended to do?

A. To determine whether the polar bear was in danger.

B. To measure how fast the sea ice melts in the Arctic.

C. To check the predictions of the computer models.

D. To find out the exact number of the polar bear.

2.What causes the polar bears to disappear by 2050?

A. The pollution of the Arctic region.    B. The sea ice melting at high speed

C. Fewer food sources being left.         D. The temperature getting colder.

3.The key to preventing polar bears dying out seems to _______________.

A. help young polar bears to survive the cold winter

B. have large number of seals living in the oceans

C. make sure there is enough sea ice in the Arctic

D. provide chances for adult polar bears to reproduce

To swim across the English Channel takes at least nine hours. It‘s hard work and it makes you short of breath. To fly over the channel takes only twenty minutes as long as you’re not held up at the airport， but it‘s an expensive way to travel. You can travel by hovercraft （气垫船）if you don’t mind the noise and that takes forty minutes. Otherwise， you can go by boat， if you remember your sea-sickness pills. All these means of transport have their problems， and the weary（厌烦的）traveler often dreams of being able to drive to France in his own car. “Not possible， you say. Well， wait a minute. People are once again considering the idea of a channel tunnel or bridge.” This time， the great London Council（议会）is looking into the possibility of building a channel link straight to London. A bridge would cost far more than a tunnel， but you would be able to make a journey by rail or by car on a bridge， yet a tunnel would provide a rail link only. Why is this idea being discussed again？ Is Britain realizing the need for links with Europe as a result of joining EEC？Well， perhaps， the main reason， though， is that a tunnel or bridge would reach the twenty square kilometers of London‘s discussed dockland（船坞）。 A link from London to the continent would stimulate（刺激） trade and revitalize（使重新具有活力）the port， and would make London a main trading center in Europe. With a link over the Channel， you could buy your fish and chips in England and be able to eat them in France while they are still warm！

From the lines we can see that people crossed the Channel by ______ in the past.

A. air   B. boat    C. swimming   D. A， B， or C

The weary traveler thinks the best way to cross the Channel is ______.

A. by swimming   B. in his own car   C. by air  D. by hovercraft

A tunnel would cost______ a bridge.

A. far less than  B. as much as  C. far more than  D. as little as

The main idea of the passage is______.

A. how to develop the trade of London

B. when to cross the Channel

C. how to get to Europe from London more conveniently

D. what to do in the developing of traveling