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题目列表(包括答案和解析)

A rainforest is an area covered by tall trees with the total high rainfall spreading quite equally through the year and the temperature rarely dipping below l6℃.Rainforests have a great effect on the world environment because they can take in heat from the sun and adjust the climate.Without the forest cover,these areas would reflect more heat into the atmosphere,warming the rest of the world. Losing the rainforests may also influence wind and rainfall patterns,potentially causing certain natural disasters all over the world.

    In the past hundred years,humans have begun destroying rainforests in search of three major resources(资源): land for crops,wood for paper and other products,land for raising farm animals.This action affects the environment as a whole.For example,a lot of carbon dioxide(二氧化碳) in the air comes from burning the rainforests.People obviously have a need for the resources we gain from cutting trees but we will suffer much more than we will benefit.

    There are two main reasons for this.Firstly,when people cut down trees,generally they can only use the land for a year or two.Secondly,cutting large sections of rainforests may provide a good supply of wood right now,but in the long run it actually reduces the world’s wood supply.

    Rainforests are often called the world’s drug store.More than 25% of the medicines we use today come from plants in rainforests.However,fewer than l%of rainforest plants have been examined for their medical value.It is extremely likely that our best chance to cure diseases lies somewhere in the world’s shrinking rainforests.

Rainforests can help to adjust the climate because they                

  A.reflect more heat into the atmosphere

  B.bring about high rainfall throughout the world

  C.rarely cause the temperature to drop lower than l6℃

  D.reduce the effect of heat from the sun on the earth

What does the word “this” underlined in the third paragraph refer to? 

  A.We will lose much more than we can gain.

  B.Humans have begun destroying rainforests.

  C.People have a strong desire for resources.

  D.Much carbon dioxide comes from burning rainforests.

It can be inferred from the text that      

  A.we can get enough resources without rainforests

  B.there is great medicine potential in rainforests

  C.we will grow fewer kinds of crops in the gained land

  D.the level of annual rainfall affects wind patterns

What might be the best title for the text? 

   A.How to Save Rainforests                B.How to Protect Nature

   C.Rainforests and the Environment        D.Rainforests and Medical Development

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A new study by Penn State College of Medicine research team found that honey is a better and safer treatment for children than cough medicines.

   Ian Paul, the study’s lead researcher, was motivated to test honey because treating coughs in children has recently become a sticky subject. Coughing is the body’s way of cleaning irritated (受刺激的) airways to help you breathe. But too much coughing can irritate your lungs and throat even more. It can also make it tough to get the sleep your body needs to heal. Hoping to ease the suffering of their children, parents often give them cough medicines.

But there have never been any good studies showing that they work. Cough and cold medicines may also cause serious side effects. Hundreds of kids die in the hospital each year after receiving too much cough medicine by mistake. Last October, the US Food and Drug Administration suggested that parents should not give cough medicines to children under 6.

In order to search for a different solution, Paul designed a study that involved 105 kids who were sick with coughs and other cold conditions. At bedtime, the kids took buckwheat(荞麦) honey, honey-flavored (蜜蜂味的) DM (one of the most common ingredients成分in cough medicine), or no treatment. Parents and kids in the no-treatment group knew they weren’t getting anything, but the other two groups weren’t told which treatment they were getting.

The surveys showed that kids who swallowed about 2 teaspoons of buckwheat

honey before bedtime coughed less and slept better than kids in other groups.

“When parents want something for their kids to take,” Paul says, “honey seems

 like the best option.”

But what gives honey its healing power? Substances called antioxidants(抗氧化剂) may be part of the answer. All honey contains antioxidants that protect our cells from damage. Studies show that antioxidant levels in the body rise after someone swallows honey.

Which of the following can be the best title for this passage?

A. Sweet solution to kids’ coughing

B. No cough medicines to children

   C. Best treatment for your cold

   D. Cough medicines don’t work

We can learn from Paragraph 2 that coughing ______.

   A. can cure lung and throat diseases

   B. is more harmful to children

C. sometimes does good to people 

   D. helps improve children’s die

During Paul’s experiment, the kids who received treatment __________.

   A. seemed much worse than before

B. had no idea what they swallowed

C. knew they weren’t getting anything

   D. coughed less and slept better

According to the passage, Paul’s experiment proved that ____.

A. honey may have real healing power

B. cough medicines may cause side effect

    C. cough medicines don’t really work

D. buckwheat honey contain more antioxidants

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A mobile phone is no longer just a phone -- it is also a music player, video camera and personal organizer. And mobile phones with television programming are just around the corner. But the more functions cell phone manufacturers add, the greater the amount of power the phones use and the less practical running them on lithium (锂) batteries becomes -- so the race to find a viable alternative is on.

    Two of the world's biggest electronics makers, Hitachi and Toshiba, are currently competing against each other to come up with an alternative, most likely to be micro fuel cells. The task has been set by Japan's second largest mobile phone provider, KDDI, which wants its customers to soon be able to use special television programming on their handsets, and has asked the two electronics companies to come up with a better power source. Hitomi Murakami, of KDDI, says battery-operated mobile phones cannot keep up with the new applications. "We're looking at various ways to expand content and services that we can provide to the people. And we don't want to have battery issues delaying us from doing that," he says.

    Hitachi's Atsushi Morihara says it is a critical race for both of the companies as the resulting product will have a major impact on the mobile market in the future. "We are in competition and it's up to both of us to come up with a good product. A product that will satisfy KDDI's needs. I think I can go as far to say that the winner will take all."

    Miniaturized direct methanol (甲醇) fuel cells are different batteries in that they create power instead of simply storing it. That power is made by new technology utilizing cheap methanol. If all gees to plan, come 2007, Japanese phone users will not use an electric charger to power their mobiles, they will instead carry a small bottle of methanol and with just a few squirts, they will have power for their phones. But the method has its downsides, including how passengers will be able to take small mounts of flammable methanol on airliners. Fumio Ueno of Toshiba says that once developed, the uses of miniaturized direct methanol fuel cells have endless possibilities.

The lithium batteries are becoming improper for the cell phone because ______.

     A) there is a television in the phone         C) it is inconvenient to use

     B) it can't provide enough power              D) people have found substitutes

According to the passage, Toshiba ______.

     A) is in critical competition with KDDI

     B) will probably beat its rival

     C) attaches great importance to methanol fuel

     D) is one of the largest battery provider

Which of the following is NOT the characteristic of methanol fuel?

     A) Easy to catch fire.                         C) Portable.

     B) Inexpensive.                              D) Available everywhere.

The best title for the passage is ______.

     A) Search for better phone power.

     B) Development of cell phone battery.

     C) Competition between two electronic firms.

     D) Advantage and disadvantage of methanol fuel.

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A young British sailor was missing at sea yesterday in similar circumstances(情况)to the way his father died five years ago.

   The dinghy(救生橡皮船),used to take Richard Smith,21,to his yacht(快艇),was discovered empty, floating in seas off the Caribbean island.An air and sea search was carried out but he has still not been discovered.

  Richard’s mother, Bicknell,said from her home in Hampshire,“It’s so much coincidence.Richard always carried a photograph of his father attached to a poem,which included the date of his disappearance.”

  “Now, it’s very strange because all they have found is Richard’s dinghy.We need to know this time what has happened one way or another.If you know at least you can go through the grieving process(悲痛的过程).”

  In November 1996,Mr. Smith’s father, Charlie,was sailing in the Tasmen sea between the Australian mainland and the island of Tasmen with his new wife.They lost radio contact with the shore and they, together with their yacht were never seen again,and their disappearance remains a mystery.

  Richard is described a talented(有才能的)and experienced sailor who has crewed for the champion ocean racer.He had sailed to the。Caribbean in November to crew ocean racing yachts for entertainment.He ended the evening drinking in the Abracbabra bar but left after local police closed it for being too noisy.

  About 2 am the following day Richard headed back for his dinghy.He started its outboard motor before giving all elderly woman a lift to her yacht after her dinghy had gone missing.It was the last time he was seen.

Riehard Smith was       in 2000.

A.ten    B.fifteen    C.twenty    D.eighteen

People searched for Richard using      .

 A.ship only   B.ship and radio C.ship and plane   D.yacht and car

According to the passage,we know Richard died because        .

A.he was a green hand in sailing

B.some unknown animal attacked him

C.that was a maze in the area he was sailing

D.of something we don’t know

Which statement is NOT true according to this passage?

A.Young Smith had lost radio contact with the shore before he died.

B.Richard’s father had married two women at least.

C.Richard didn’t drink on the evening before he was lost because the

policeman closed the bar.

D.Richard was seen at about 2 am the day he disappeared.

The writer tells us     .

A.a story about two heroes     B.a piece of news about a merchant ship

C.a coincidence              D.the dying process of Richard

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For hundreds of years humans have dreamt of finding life on distant planets. Now the hope of discovering real evidence of life has greatly increased

NASA’s Mars detector (探测器), Opportunity, succeeded in finding signs that water once existed on the planet. Opportunity landed on Mars in January. Scientists now believe that the planet could once have supported life.

This discovery was chosen by Science, one of the world’s leading magazines, as the most important scientific achievement of 2004 last Friday

“This little, wheeled, one-armed box went around another planet and has done something no human has ever managed,” according to Science. “It has discovered another place in the universe where life could once have existed.”

“Although we still can’t say that life could have existed in this environment, it is now certain that there was water on Mars,” said Steve Squyres, one of the scientists working on the Mars mission. The evidence comes from pictures and chemical readings taken by Opportunity. It includes marks on rocks like those caused by flowing water on Earth and salty chemicals like those found in dried-out sea-beds. Scientists said the new evidence proved beyond doubt that water has been existed on Mars. But it is still unknown whether the water on Mars was like an ocean or just ice.

While Opportunity has not found any signs of life, the presence of water means life is possible. “In everything we know about life on Earth, there is no example without liquid water,” Squyres said. “So water is important for the search for life on Mars.”

Researchers agree that a future mission (任务) should bring back physical samples (样品). But some scientists worry about the risk that this could introduce dangerous foreign creatures to Earth. “The problem here is how to get the samples back,” Squyres replied. “I think it is our responsibility to limit any risk.”

1. ________ prove that water existed on Mars.

A. The physical samples with salty chemicals            

B. The marks on rocks and salty chemicals

C. Scientific achievements of 2004                          

D. Creatures from Mars

2. Which of the following is true according to the text?

A. It is now certain that there was water on Mars.             

B. The water on Mars was like an ocean.

C. Evidence of life on Mars has been found.                    

D. Search for life on Mars is a great risk to humans.

3. How did scientists draw the conclusion that there was water on Mars?

A. The world’s leading magazine has announced the fact.

B. Scientists have taken many pictures and chemical readings on the Mars.

C. Astronauts have got some rocks from Mars.

D. Scientists have made a study of the pictures and readings sent back by Mars detector.

4. It can be inferred that, if the creatures from Mars came to Earth, ________.

A. they would be kind to humans                   

B. they would be cruel to humans

C. they would be a great danger to Earth

D. it would be hard to say whether it would be a good news or bad news

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