There is not enough oil in the world now. As time goes by ,it becomes less and less ,so what are we going to do when it runs out? Perhaps we will go back to use horses ,carriages and bicycles .

In the Second World War ,some people didn＇t use gas made from petroleum （石油）in their cars .They made gas from wood and plants instead . The cars didn＇t go fast ,but they ran ,so this was better than nothing. However, in the future, we can＇t cut down all our trees to make gas; we need our trees for other things, too.

Besides different types of gas, we can also use electricity(电)to run our cars but first we must make the electricity ！Some countries have coal and they make electricity with that, but we might not always have coal, either. Other countries have big ,strong rivers and they can use the power of water to turn turbines(涡轮机) and make electricity more easily and cheaply.

We are also able to get power from the ocean tides. We put turbines into the mouth of the river .Then the tide comes in ,the water turns the turbines and then it goes out ,it turns them again.

Which of these ways will be used to run our cars in the future?

小题1:When might people have to go back to using horses and carriages?

A．When they are poor

B．When they run out of oil

C．When they need more exercise

D．When there aren＇t any big trees in the world小题2:How many ways are suggested to make electricity in the passage?

A．2

B．5

C．4

D．3小题3:The passage is mainly about             .

A．how to run our cars

B．what to do when oil runs out

C．different types of gas

D．the way to make electricity

B

Unless we spend money to spot and prevent asteroids (小行星) now，one might crash into Earth and destroy life as we know it，say some scientists.

Asteroids are bigger versions of the meteoroids(流星)that race across the night sky. Most orbit the sun far from Earth and don't threaten us. But there are also thousands whose orbits put them on a collision course with Earth.

Buy $ 50 million worth of new telescopes right now. Then spend $ 10 million a year for the next 25 years to locate most of the space rocks. By the time we spot a fatal one，the scientists say，we'll have a way to change its course.

Some scientists favor pushing asteroids off course with nuclear weapons. But the cost wouldn't be cheap.

Is it worth it? Two things experts consider when judging any risk are: 1) How likely the event is; and 2) How bad the consequences if the event occurs. Experts think an asteroid big enough to destroy lots of life might strike Earth once every 500，000 years. Sounds pretty rare-but if one did fall，it would be the end of the world. “If we don't take care of these big asteroids，they'll take care of us，”says one scientist. “It's that simple.”

The cure，though，might be worse than the disease. Do we really want fleets of nuclear weapons sitting around on Earth? “The world has less to fear from doomsday(毁灭性的) rocks than from a great nuclear fleet set against them，” said a New York Times article.

1. What does the passage say about asteroids and meteoroids?

[ A ]. They are heavenly bodies different in composition.

[ B ].They are heavenly bodies similar in nature.

[ C ].There are more asteroids than meteoroids.

[ D ].Asteroids are more mysterious than meteoroids.

2. We can conclude from the passage that_____ .

[ A ].while pushing asteroids off course nuclear weapons would destroy the world

[ B ].asteroids racing across the night sky are likely to hit Earth in the near future

[ C ].the worry about asteroids can be left to future generations since it is unlikely to happen in our lifetime

[ D ].workable solutions still have to be found to prevent a collision of asteroids with Earth.

3. Which of the following best describes the author's tone in this pass age?

[ A ]. Optimistic.  [ B ]. Critical.  [ C ]. Objective.  [ D ]. Arbitrary.