How does the cog railroad differ from a regular railroad? A. It has a scenic view. B. It is controlled by a computer. C. It climbs steep hills. 查看更多

 

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Can you tell me ______?

A.what does the island look like

B.what the island looks like

C.how does the island look like

D.how the island looks like

 

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Have you ever wondered why birds sing? Maybe you thought that they were just happy.After all, you probably sing or whistle when you are happy.

Some scientists believe that birds do sing some of the time just because they are happy.However, they sing most of the time for a very different reason.Their singing is actually a warning to other birds to stay out of their territory.

Do you know what a "territory" is? A territory is an area that an animal, usually the male, claims as its own .Only he and his family are welcome there .No other families of the same species are welcome.Your yard and house are your territory where only your family and friends are welcome.If a stranger should enter your territory and threaten you, you might shout.Probably this would be enough to frighten him away.

If so, you have actually scared the stranger away without having to fight him.A bird does the same thing.But he expects an outsider almost any time, especially at nesting (筑巢) season.So he's screaming (高声尖叫) all the time, whether he can see an outsider or not.This screaming is what we call a bird's song, and it is usually enough to keep an outsider away.

Birds sing loudest in the spring when they are trying to attract a mate and warn others not to enter the territory of theirs.You can see that birds have a language of their own.Most of it has something to do with attracting mates and setting up territories.

1.Some scientists believe that most of the time birds' singing is actually

A.an expression of happiness                        

B.a way of warning

C.an expression of anger                          

D.a language of their own

2.What is a bird's "territory"?

A.A place where a bird may shout at the top of its voice.

B.A place where other bird families are not accepted.

C.An area for which birds fight against each other.

D.An area which a bird considers to be its own

3.Why do birds keep on singing at nesting season?

A.Because their singing helps frighten outsiders away.

B.Because their singing helps get rid of their fears.

C.Because they want to find outsiders around.

D.Because they want to invite more bird friends.

4.How does the writer explain birds' singing?

A.By comparing birds with human beings.            B.By reporting experimental results.

C.By describing birds'daily life.                    D.By telling a bird's story.

 

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Everybody hates rats.But in the earthquake capitals of the world-Japan,Los Angeles,Turkey-rats will soon be man's new best friends.

What happens after an earthquake? We send in rescue(救援) dogs. Why? Because they can smell people.Dogs save lives.They help rescuers to find living people.But dogs are big and they can't get into small spaces.So now a new research project is using a smaller animal to save lives:the rat.

How does it work? First,the rat is trained to smell people.When this happens,the rat's brain gives a signal(信号).This is sent to a small radio on its back,and then the rescuers follow the radio signals.When the rat's brain activity jumps,the rescuers know that someone is alive.The rat has smelled that person.

Although there are already robots which can do this job,rats are better.Christian Linster at Cornell University—New York says,“Robots' noses don't work well when there are other smells around.Rats are good at that.” Rats can also see in the dark.They are cheaper and quicker to train than dogs,and unlike robots,they don't need electricity!

The “rat project” is not finished,but Julie Ryan of International Rescue Corps in Scotland says,“It would be fantastic.A rat could get into spaces we couldn't get to and a rat would get out if it wasn't safe.” Perhaps for the first time in history,people will be happy to see a rat in a building(but only after an earthquake,of course).

1.In the world earthquake capitals,rats will become man's best friends because they can _________.

A. take the place of man's rescue jobs

B. find the position of people alive who are trapped in buildings

C. serve as food for people alive who are trapped in buildings

D. get into small spaces

2.From the third paragraph we know the rescuers can judge a person is alive by_________.

A. the noise made by the rat                    B.the rat's unusual behavior

C. the signal sent by the radio on the rat's back   D.the smell given off by the person

3. In doing rescue jobs,_________.

A. rats smell better than dogs

B. dogs don't need to be trained to smell people

C. robots' sense of smell can be affected by other smells around

D. rats can see in the dark and smaller than robots

4. Rats have all the following advantages except that_________.

A. they are more fantastic than other animals       B. they are less expensive to train than dogs

C. they don't need electricity                  D. they are small and can get into small places

 

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(二)

A

How Do Animals Catch Their ZZZ’s?

Different creatures have developed some pretty creative ways to get their rest and stay safe. The lizard(蜥蝎)likes to sleep at the far end of small branches hanging out over a pond or lake in the rain forest. If a snake tries to slither up the branch to eat it ,it will shake the branch and knock the lizard off ,and the lizard will fall safely into the water. Chameleons can change color to match their surroundings in order to hide even while sleeping.

Corillas(大猩猩)like to sleep high in the trees. They build a new bed every night, sometimes taking up to half an hour to pile branches ,twigs ,and leaves into a comfortable bed .Birds also find it safe to sleep in the trees, but unless they have eggs or young chicks ,they don’t use a nest .They just lock their feet around a branch and hang on .A special tendon(腱)in their legs in automatically tight when they are at rest ,so they won’t let go and fall.

Dolphins live underwater ,but must come to the surface to breather .Scientists now believe that dolphins may sleep with only half their brain, while the other half stays awake to keep them safe and breathing. Seals also do this ,lying on their sides on the surface of the water with one flipper underwater paddling to keep their noses above the surface. Some ducks may also have this ability, and actually sleep with one eye closed and one eye open.                          

56.How many animals are mentioned in this passage?

A.6.                       B.7.                       C.8.                       D.9.

57.How does a chameleon protect itself while sleeping?

A.By changing its body colors.                 B.By hinging out over a pond.

C.By sleeping with half their brain.          D.By making beds with branches.

58.Why will not birds fall when they are at rest?

A.They build nests and sleep in them.       B.They fall asleep automatically.

C.They have a loose tendon in their legs.   D.They lock their feet around a branch.

59.What does the writer intend to tell us?

A.The cleverest animal is the gorilla because it can make beds.

B.Differences in habitat could lead to different living habits.

C.The ways animals catch their ZZZ’s are pretty much he same .

D.In order to protect themselves most animals choose not to sleep.

 

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With alarming regularity, we read about oil tankers having accidents near land and the terrible consequences of the oil spills(泄露) on people, nature, and the environment.

       Millions of dollars have been used in developing special chemicals to help dismiss the spills and to clean up the animals, beaches, and land spoiled by the oil. Unfortunately, when many of these chemicals are used, more damage is caused to the environment, especially to lives in the sea.

       Of all of today’s environmental disasters, an oil spill may actually be one of the least serious. Although oil is poisonous, it is a natural material. In the end, it breaks down naturally. There are, of course, long-term effects, but it is usually more serious in the short term.

       Nature by itself works better than chemical materials, but when there is a spill we demand that governments act immediately with as much hi-tech knowledge as possible. In 1967 the tanker Torrey Canyon sank off the Scilly Isles near the coast of England and spilled 120,000 tones of oil into the ocean. If you go there today, you will find it hard to see any sign that it ever happened.

       Governments seem to accept the risk of transporting millions of tons of oil by ship every day so that we can fill up our cars and drive around and cause even more environmental damage. Interestingly, the biggest companies in the world produce cars, and the next biggest supply the gasoline to make them run!

       We should be thinking more about reducing our dependency on oil. Governments should be encouraging research into new technologies, such as cars run by solar power(太阳能), electricity, hydrogen, and so on. Much of this research has, in the past, been held back by the oil, gas, and coal.

       If the world’s millions of cars were 10% more efficient(高效的) — and the industry could easily produce cars at least twice as efficient — we would need many fewer tankers crossing the oceans each year. If this happened, the risks of oil spills would be reduced, and the air we breathe would be cleaner and fresher, too.

What is the passage mainly talking about?

   A. Oil spills pollution.                                            B. What oil pollution is.

C. Oil tanker accidents.                                     D. How to reduce oil pollution.

How does the author support the idea that oil spills are not as serious as people believe?

A. By giving a description.                                    B. By making an argument.         

C. By giving an example.                                        D. By drawing a diagram.

What does the underlined word “risk” in Paragraph 5 refer to?

A. Transportation depending more on oil.      B. Poisonous oil breaking down naturally.

C. Millions of tons of oil spilling into the sea.   D. More environmental damage being caused.

Which suggestion is made for reducing oil tank accidents according to the passage?

A. We should build safer oil tankers in the near future.

B. We should develop new technologies to cut oil use.

C. Tankers should not be allowed to sail near the coastlines.

D. Countries should build more oil pipelines under the sea.

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