27. From the passage, we can learn that in Germany _______.

A. all kinds of high schools are for college

B. age is not important for attending schools

C. students can take part in after-school activities from 8:00 a. m .to 3:30 p.m.

D. students can join private clubs to meet their interests by themselves

B

Every time you turn on the television or take a ride in a car ,you could be adding to a problem called acid rain(酸雨). In this article, you’ll learn how acid i s created, and how it affects us, and more importantly, what we all can do to prevent it.

How is  acid rain created?

When people use fuels(燃料), such as coal and gasoline, poisonous gases are given off. When these gases mix with rain, acid rain forms. Many power stations burn fuels in order to create the electricity(电) that we use in our homes and offices every day. Cars and trucks also send these gases into the air when they burn gasoline .When rain mixes with these gases, harmful things called acids form. This is acid rain.

How does acid rain affect us?

Acid rain damages(毁坏)everything that it touches . It poisons our rivers, ponds, lakes, and oceans along with all the life in them. It pollutes our soil and crops, harms trees, and can even kill fish and plants. Acid rain also eats away at buildings.

How can we prevent acid rain?

We need to cut down on the pollution that gets into our air. Turn off lights, television, and other electrical appliances if you are not using them, Walk or take a bike whenever possible. If you are travelling a long distance, take a bus or train to save fuel.

As research shows, acid rain harms our environment. But people everywhere can take small steps now to help protect our environment for future generations.

28. When power stations burn fuel, _______.

A. acid rain form                   B. air pollution is caused

C. noise pollution is caused           D. acid rain gets heavier

29. What advice does the article give us?

A. Go to school on foot or by bike if we can.

B. Go to bed earlier in order to use less electricity.

C. Travel by bus to prevent acid rain.

D. Turn off the television on rainy days.

30. What is the best title of the article?

A. Preventing Acid Rain                    B. Forming of Acid Rain

C. Acid rain, Heavy Rain                   D. Acid Rain, Killer Rain

C

Look carefully at the back of a California state quarter. A man with a walking stick is pictured there. A bird called a California condor(大秃鹫)is flying overhead. Who is this man, and why is he so important that he is featured(处于显著地位)on the back of a coin?

The man on this quarter is J ohn Muir. Even as a child, Muir loved watching nature. As a young man, he spent much of his life exploring the beauty of the wilderness. He walked more than a thousand miles across the country, through fields and woods. John Muir liked writing about the places he visited, describing their beauty.

Muir also wrote about problems. In order to create more farmland for sheep and cattle, many trees were being cut down. This made Muir unhappy and worried, because he knew that trees were important to forests and to the animals that lived in them.Muir believed that nature should be conserved(保护)instead of being changed by human beings. He wrote articles in magazines and newspapers to spread the word about conserving forests. Soon, others began to listen.

Muir wrote letters to important people, such as President Theodore Roosevelt. The president admired Muir’s love for nature. When Roosevelt came to visit Muir in California. Muir convinced(说服)the president to go camping with him for three nights under the trees so they could talk about conservation. Later, President Roosevelt set aside 148 million acres of land for national forests and established(建立)five national parks. National parks are large areas of land that are protected from development. This means that people cannot build homes or businesses there. One of these parks is Yosemite National Park, the area that is featured  on the back of the California quarter.

Though it has been almost one hundred years since John Muir died, people continue his work today. His work as a conse rvationist helped us to see the beauty of our natural world. John Muir made us understand the importance of protecting our earth and our resources---then, now, and for the future.

31. Why did President Theodore Roosevelt visit John Muir?

A. Because Roosevelt loved watching nature.

B. Because Roosevelt received letters from John Muir.

C. Because Roosevelt admired John Muir’s love for nature.

D. Because Roosevelt was sad about the problems with farmland.

32. Why is John Muir featured on the back of a California state quarter?

A. Because he walked over a thousand miles across the country.

B. Because he helped people understand the importance of protecting the natural world.

C. Because he wrote articles to spread the word about conserving forests.

D. Because he once wrote several letters to President Theodore Roosevelt.

33. What is the writer’s purpose of writing this article?

A. To advise readers to become active conservationists.

B. To make us interested in the story about a great man.

C. To tell us something about an important person in history.

D. To give information about how to conserve the environment.

D

After spending years searching for a planet with life, scientists may have found one. In September 2010, a team of US scientists discovered an Earth-sized planet called Gliese 581g. It has a surface temperature neither too hot nor too cold for liquid(液态)water. Scientists think there is a chance that the planet could have life.

The planet Gliese 581g goes around a star called Gliese 581, which is about 20 light-years from Earth. That is about 194 trillion(万亿)kilometres -500 million times farther away from us than the moon.

A spacecraft traveling at a one-tenth of the speed of light would reach Gliese 581g within about 220 years. A human can’t live that long, but robotic explorers could make the job easier. However, our fastest spacec raft don’t come anywhere near that one-tenth light-speed mark.

At present, scientists don’t know what the surface might be like on Gliese 581g. What they know is that the planet is at the right distance from its star to have liquid water. It’s also at the right distance to have an atmosphere that could protect the water if it is on the surface.

Although spacecraft won’t be getting there anytime soon, one way to look for life on Gliese 581g is to turn our radio telescopes(望远镜)towards the planet and search for radiation(放射). By studying the radiation, scientists would find out about the chemicals(化学物质)around the planet and discover if Gliese 581g has an atmosphere. If it has one, studying the atmosphere would give us a good idea whether the planet has life or not. But it’ll probably be many years before we can do this properly.

People have been arguing about whether there is alien life on Gliese 581g. Any discussion about alien life is just guessing at this point, according to its discoverers.

34. What did scientists find in September 2010?

A. A planet with water.     B. A planet similar to the earth.

C. A planet without life.     D. A planet near the earth.