Scientists have found what look like caves on Mars, and say they could be protecting life from the planet’s terrible environment.
The first caves discovered beyond the Earth appear as seven mysterious black dots on the pictures sent back by NASA’s Mars Odyssey orbiter. Each as large as a football field, they may be openings into natural caves below the Martian surface.
“If there is life on Mars, there is a good chance you’d find it in caves,” said Jut Wynne, one of the researchers who noticed the features while working on a US Geological Survey Mars Cave Detection Program.
Jonathan Clarke, a geologist with the Mars Society of Australia, yesterday described the discovery as exciting.
One photo taken at night by an infrared imager(红外线成像器) showed one hole to be unusually warm, suggesting hot air trapped during the day is flowing out.
“I said: ‘Wow, that’s a cave’.” Dr. Clarke said excitedly. “People have been looking for these for a long time; now we have found them.”
He agreed such caves would be perfect places to hunt for life escaping from the bitterly cold, radiation-soaked(充满辐射的), dry surface.
“Tiny drops of water could collect inside,” he said. “If there are gases coming out, they could provide energy for a whole range of bacteria. A cave is also a protection from radiation; the surface of Mars is exposed to high levels of space radiation.”
The caves probably formed when tube-shaped lave flows(管状岩浆流) spread across the planet long ago. The outside of the tubes cooled, forming solid walls, while something hotter inside allowed the remaining have to flow out, forming caves.
What does the passage mainly talk about?
| A．How the caves were formed on Mars. |
| B．How scientists found these caves on Mars. |
| C．Caves on Mars may be full of hot air or a sign of life. |
| D．Scientists have completely recognized the surface of Mars. |
What can the “cave” be used for according to the scientists?
A. They can protect life from the planet’s terrible environment.
B. They can provide energy for people’s life.
C. They can be used to prevent space radiation
D. Both A and C.We can learn from the passage that .
| A．water has already been found on Mars |
| B．the scientists found all the caves at night |
| C．it is certain that there is life in these caves |
| D．the surface of Mars is bitterly cold, radiation-soaked and dry |
According to the passage, Dr. Clarke was so excited because .
| A．such caves could provide energy for life |
| B．they had finally found the caves on Mars |
| C．such caves would be perfect places to hunt for life |
| D．scientists had long been looking for these caves |
Necessary conditions for life on Mars mentioned in the passage may include .
| A．lave and energy |
| B．water and radiation from space |
| C．gases and lave |
| D．water and protection from radiation |
Many people may not believe it, but this is what is happening: polar bears are dying out! They are dying because they are losing a great deal of habitat due to human incursion（侵入）and global warming. They are dying because of starvation as well. With the sea ice they depend on for survival shrinking, it is becoming increasingly difficult for them to find food.
An ecosystem is highly dependent on all of its parts, and removing even a single species can result in serious consequences. Polar bears are at the top of the predators（捕食性动物）where they live. They play an important part in the ecosystem. They feed on seals, fish and deer. Several other animals depend on the kill of polar bears. The failure to save polar bears might result in loss of these predators.
In addition, all large predators perform a very important function in their habitat: helping to control the populations of other species. When an animal group loses its natural predators, its population will rise rapidly, having a direct result in population decrease of other groups. A huge boom in population of Arctic seals would have a direct effect on the prey(捕食) of seals, and could reduce numbers of certain types of fish.
This could also have a direct effect on humans, who might have to compete with Arctic seals for food supplies from fish. Lack of polar bears could eventually affect human food supply. Human beings shall save polar bears to ensure the food supply.
There is no doubt that we should save polar bears. However, there is still another question: can they be saved? This is a matter that scientists debate because of rapid degradation（恶化）of the polar bear’ environment in recent years due to warming temperatures. It is estimated that if the bears cannot adapt to changing climates, they might die out before the end of the 21st century, with about 50% of the animals disappearing by 2050. So time is running out!
There are some things that may help slow down global warming and help delay extinction of polar bears. These include finding new energy sources that don’t give off greenhouse gases and not making any more incursions into polar bear’s territory.
Which is NOT the threat to the survival of polar bears according to the passage?
| A．Human’s killing. | B．Global warming. |
| C．Habitat loss. | D．Lack of food. |
Why do we need to save polar bears?
| A．For the predators in the ecosystem. |
| B．For the seals in Arctic Circle. |
| C．For our own source of food. |
| D．For our environment. |
If bears can’t adapt to changing climates, we will probably have lost _____ by the middle of the 21st century.
| A．half of polar bears |
| B．most of polar bears |
| C．90% of polar bears |
| D．all of polar bears |
We can infer that _____ .
| A．nothing can prevent the extinction of polar bears |
| B．drilling for oil in the Arctic should be encouraged |
| C．polar bears can surely adapt to changing climates |
| D．using solar energy is good for saving polar bears |
Bob was born in Cambridge. When he was in elementary school, he asked his mother to take him to parks in their community so he could collect empty soda cans to recycle. His mother agreed, as long as he saved part of the money he earned for college.
Bob’s mother remembers Bob as the most determined of her seven kids. Bob’s persistence paid off. On Friday, he will become the first person in his family, originally from El Salvador, to graduate from college. And he’s graduating with university honors.
For his honors thesis（毕业论文）he researched unmanned solar-powered airplanes, which BYU students have been building and testing for about 10 years. Bob’s study helps discover the best way to fly a solar-powered airplane so that it uses the least amount of power. The goal is to design and build an airplane that flies indefinitely. Bob’s thesis helps lay the foundation for this work.
“My parents were always diligent,” Bob said. “They often tell us hard work leads to success. ” Bob’s father taught him to read at the age of 3, and his mother is currently a student at Utah Valley University in a way to becoming a dentist.
Bob acknowledges he overcame some obstacles to get where he is. For starters, English is his second language. He also faced stereotypes（模式化的形象）. Although Bob never doubted that he would be a college graduate, other people assumed he wouldn’t because he didn’t come from a family of high income. There were other obstacles as well, but Bob viewed them all as opportunities.
Bob’s mother says she feels very happy and proud that her son is about to graduate with honors, and remembers the sacrifices he’s made to get there. “He has worked very hard. He started something, and now he has finished it,” Cathy says. “I have always told him, ‘If this is your dream, then you can get it! Keep working hard and you can get it!’”
From the passage we can know that Bob’s honors thesis _____ .
| A．makes his mother feel surprised |
| B．helps to save the power of flying a solar-powered airplane |
| C．is done with BYU students |
| D．doubts the way of flying a solar-powered airplane |
According to the passage, Bob _____ .
| A．researched unmanned solar-powered airplanes for 10 years |
| B．paid for all his study by collecting empty soda cans |
| C．worked hard and has graduated from college |
| D．was affected by his family and has made some achievements |
People thought Bob couldn’t graduate from college because _____ .
| A．his parents had little money to support him |
| B．his teacher didn’t think he could graduate |
| C．he didn’t work hard on his study |
| D．he didn’t dare to face the obstacles for short of confidence |
It can be inferred that _____ .
| A．Bob’s mother is in a way to becoming a dentist |
| B．Bob’s mother works in their community |
| C．Bon’s father will graduate from Utah Valley University on Friday |
| D．Bob’s father learnt to read at the age of 3 |
Britain's most popular lie has been disclosed, with one in four people admitting using “sorry I had no signal" when returning a missed mobile phone call, a survey found.
Researchers found the average Briton tells on average four lies every day or almost 1500 every year. Almost one in six men admitted they were most likely to lie to their wife or girlfriend, on average at least twice a day. The most popular lie was saying you had no mobile phone signal, with one in four people admitting regularly using the little white lie. It usually came after they hit the “ignore" button when their mobile rang.
Three quarters of people think women are better liars. The research found 46 per cent of girls have been caught lying, compared to 58 of men.
The second most common fib is “I haven't got any cash on me” when asked for money by beggars and Big Issue sellers. “Nothing's wrong – I'm fine” came third followed by “You look lovely” and “Nice to see you”.
Modern technology turned out to have contributed to many lies with “I didn't get your text” in 18th, “Our server was down” in 20th and “My battery died” in 26th place. Other lies to make the top ten included “I'll give you a ring”, “We're just good friends” and “We'll have to meet up soon”. “I'm on my way” and “No, your bum doesn't look big in that” completed the top ten.
In many cases perhaps it is better to delight someone with a fib than destroy someone with the truth, according to a spokesman for OnePoll, which carried out the research of 4,300 adults. He added: ‘As a nation we just like trying to be nice and not upsetting people. Often little white lies can cover what we actually want to say. Most of these were considered completely harmless. ’
“You look lovely” and “Sorry, I had no signal” ranked __________ on the popular-lie list.
| A．fourth and tenth | B．fourth and first |
| C．third and tenth | D．third and first |
What does the underlined part in Paragraph 4 mean?
| A．sentence | B．expression | C．excuse | D．lie |
How many lies does an average Briton tell on average every month?
| A．About 120 | B．About 360 |
| C．About 1,500 | D．About 4 |
Why do British people like telling lies, according to the spokesman for One Poll?
| A．Because truth will destroy others. |
| B．Because British people are very considerate. |
| C．Because it’s easier for others to understand lies. |
| D．Because lies were harmless. |
Learning a second language can improve brain power, scientists believe. US researchers from Northwestern University say bilingualism(双语) is a form of brain training — a mental "work out" that adjusts the mind finely.
Speaking two languages well affects the brain and changes how the nervous system reacts to sound, lab tests showed. Experts say the experiment performed by the National Academy of Sciences provides "biological" evidence of this.
In an attempt to prove the guess that speaking two languages is good for one's mind, the team monitored how the brain of 48 healthy student volunteers reacted to different sounds. Twenty three of these volunteers were bilingual.
The scientists used special equipment to trace the pattern of brainwaves. Under quiet, laboratory conditions, the bilingual students responded in a similar way to the English-only-speaking students, who formed the control group. But the bilingual group were far superior at processing sounds even when there were a lot of people talking in the room. They were better able to focus on to the important information — the speaker's voice — and block out other distracting noises.
Prof Nina Kraus, who led the research, said: "The bilingual's better experience with sound results in a hearing system that is highly efficient, flexible and focused in its automatic sound processing, especially in challenging or novel listening conditions."
Co-author Viorica Marian said: "People do crossword puzzles and other activities to keep their minds sharp. But the advantages we've discovered in double language speakers come automatically simply from knowing and using two languages.''
Musicians appear to gain a similar benefit when rehearsing(彩排), say the researchers. According to some theories, being bilingual might help avoid dementia（痴呆）.What’s the purpose for the lab test led by Prof Nina Kraus?
| A．To find how better the bilingual students can react to sound than other students. |
| B．Just to find scientific proof for a previous guess. |
| C．To show the students how good it is to learn a second language. |
| D．To find a way to prevent dementia. |
What does the underlined word “distracting” mean?
| A．tiring | B．exciting |
| C．interesting | D．disturbing |
What does Viorica Marian seem to believe?
| A．People should do crossword puzzles to keep their minds sharp. |
| B．Bilingual students have more advantages in study than non-bilingual ones. |
| C．Speaking two languages is an easier way for people to increase their brain power. |
| D．Bilingual students are better at solving crossword puzzles. |
What conclusion could be drawn from the passage?
| A．Being bilingual strengthens brain power. |
| B．Speaking a second language can change your nervous system. |
| C．Bilingual musicians perform better on stage. |
| D．The English-only-speaking students can concentrate easily. |
How was the bilingual group better at processing sounds?
| A．They were the control group. |
| B．They could better fix their attention on something of importance. |
| C．They were able to find the speaker’s voice quickly. |
| D．They had better nervous system. |
Every year, thousands of young Europeans set off to explore their continent by train in the summertime. It is a necessary part of growing up and often the first time many Europeans travel without their parents. Now you too can share this adventure.
There are so many places you can not afford to miss while travelling in Europe: the Eiffel Tower of France, windmills of the Netherlands and the Colosseum of Rome. How do young people afford to visit everything they want?
The answer lies with the Eurail Pass. This ticket allows a traveller unlimited journeys by rail in European countries which are members of the scheme. Ambitious Chinese travellers can buy the ticket in Beijing, Shanghai and Guangzhou.
The most popular type of Eurail Pass amongst young people, according to Zhao Jiaji, from China Air Service Ltd, is the Eurail Selectpasses. With this you can design your own trip by selecting three, four or five neighbouring countries from a total 18 nations including Liechtenstein, Monaco, Hungary and Romania.
“There is plenty of choice with this pass: in total this range offers over 400 different combinations of countries to choose from!” said Zhao.
The Eurail Selectpass gives 5 to 10 travel days within a 2-month period.
For more flexibility there are the Eurail Passes which allow you to take trains in 17 countries on any day you like. It is valid (有效的)for a period of either 15 or 21 days, one, two or three months.
If you just want to travel in one or two countries to learn more about the local culture, Eurail Pass also offers two-country passes such as Spain-Portugal, France-Switzerland and Belgium-Luxemburg. And countries like Britain, France and Germany offer a kind of Eurail Pass which allows unlimited train travel in their country.
Before buying the Eurail Pass, you should know some tips to save money. The 2nd class train travel ticket is cheaper than 1st class. And youths under 26 years old or groups of 2 or more people traveling together can enjoy discounts.
For more information, please check out http://www.tt-europe.com. Why are the three tourist spots introduced in Paragraph 2?
| A．Because they are expensive places. |
| B．Because you will have to travel a long distance to visit all. |
| C．Because they are famous places for sightseeing |
| D．Because they are located in different countries |
Which of the following is not an advantage of Eurail Pass?
| A．Reasonable price. | B．Various choices. |
| C．Wide coverage. | D．All kinds of discounts. |
With the Eurail Selectpasses, you can ______.
| A．stay in Europe for 2 months or even longer |
| B．enjoy a wide range of combinations of countries |
| C．take trains on any day you like |
| D．focus your trip in one or two countries |
Which of the following is true according to this passage?
| A．Eurail Pass is a passport. |
| B．Under 26 year olds cannot buy 1st class Eurail pass. |
| C．In Switzerland you cannot use Eurail Selectpasses. |
| D．Train service is probably the first and best choice for the young to travel Europe. |
How many major kinds of Eurail passes are introduced here?
| A．Three | B．Four | C．Five | D．Six |
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