阅读下列短文，从每题所给的四个选项(A、B、C和D)中，选出最佳选项。
A
There are no signs of little green men on Mars. But new discoveries offer a bit more hope that some form of life existed there in the past --- and perhaps is still there in the present. Methane gas(甲烷) and water have been found on the Red Plane. The presence of both suggests at least the possibility of life.
According to a new report in the journal, Science, the Mars rover, Curiosity, has detected spikes of methane in the Martian atmosphere. This gas is also found in the Earth’s atmosphere, and comes from animal and plant life, as well as from the environment itself. If there’s methane in Mar’s atmosphere, where is it coming from? Scientists aren’t sure. But it marks a big change. In September 2013, Curiosity found almost no traces of methane in the Martian air. Just weeks later, however, the rover picked up a whiff of(一点点) the gas.
The scientists don’t know whether the methane spikes are caused by some form of biological matter or by the geology of the planet. Christopher Chyba, a professor of astrophysics and international affairs at Princeton, says it’s best not to be too hopeful about biology on the Red Planet. “Hopes for biology on Mars have had a way of disappearing once Martian chemistry has been better understood,” he says. “But figuring out what’s responsible for the methane is clearly a key astrobiological objective --- whatever the answer turns out to be.”
The discovery of water on Mars is nothing new. For decades, scientists have had evidence that it flowed across the surface of the planet billions of years ago. But according to another new report in Science, while the surface water on Mars seems to be long gone, there’s a lot more of it left than most of people realize.
This report is also based on findings from Curiosity. Paul Mahaffy, of NASA’s Goddard Space Flight Center in Maryland, led the study. He says there is enough water on Mars “to cover the surface to a depth of about 165 feet.”
It is not easy to reach this water. Most of it is locked up in ice at the planet’s poles.Why do scientists think there might be life on Mars?
| A．Because the Mars rover has detected water on the planet. |
| B．Because there is evidence that little green men exist on the planet. |
| C．Because the Mars rover has found some plants on the planet. |
| D．Because both methane and water have been found on the planet. |
What is the attitude of professor Christopher Chyba towards life on Mars?
| A．Optimistic | B．Negative |
| C．Neutral | D．Indifferent |
The water on Mars _______________.
| A．still flows on its surface |
| B．covers the whole planet |
| C．is locked up in ice at the planet’s poles |
| D．only existed on it billions of years ago |
In which column of a website can we read this text?
| A．Culture | B．Entertainment |
| C．Science | D．Education |
A man named Smith was sitting on his roof during a flood, and the water was up to his feet. Before long a fellow in a canoe passed and shouted, "Can I give you a lift to higher ground?"
"No, thanks," said Smith. "I have faith in God and he will save me."
Soon the water rose to Smith's waist. At this point a motor boat pulled up and someone called out, "Can I give you a lift to higher ground?"
"No, thanks, I have faith in God and he will save me."
Later a helicopter flew by, and Smith was now standing on the roof with water up to his neck. "Grab the rope, "shouted the pilot. "I'll pull you up."
"No, thanks," said Smith. "I have faith in God and he will save me. "But after hours of struggling with water, poor exhausted Smith drowned and went to his reward. As he arrived at the Pearly Gates, Smith met God and complained about this. "Tell me, God, "he said, "I had such faith in you to save me and you let me drown. What happened?"
To which God replied, "What do you want from me? I sent you two boats and a helicopter."
When the pilot asked Smith to grab the rope, ______.
| A．Smith pulled the pilot up | B．Smith did so |
| C．Smith didn't do so | D．Smith didn't hear him |
At last, poor exhausted Smith drowned and ______.
| A．went to his reward | B．passed away |
| C．went to heaven | D．all of the above |
What do we know about Smith? ______.
A. He was a lazy man
B. He was a lucky man who believed in God
C. He was a poor manWhat do you think of this passage? This passage is very ______.
A. moving B. humorous C. depressing D. surprising
D. He was a silly man who believed in God
Any mistake made in the printing of a stamp raises its value to stamp collectors. A mistake on one inexpensive postage stamp has made the stamp worth a million and a half times its original value.
The mistake was made more than a hundred years ago in the British colony of Mauritius, a small island in the Indian Ocean. In 1847 an order for stamps was sent to a London printer — Mauritius was to become the fourth country in the world to issue stamps.
Before the order was filled and delivered, a ball was planned at Mauritius’ Government House, and stamps were needed to send out the invitations. A local printer was instructed to copy the design for the stamps. He accidentally inscribed the words “Post Office” instead of “Post Paid” on the several hundred stamps that he printed.
Today there are only twenty-six of these misprinted stamps left fourteen One Penny Orange-Reds and twelve Two Penny Blues. Because of the Two Penny Blue’s rareness and age, collectors have paid as much as ＄16 800 for it.Over a century ago, Mauritius _______.
| A．was an independent country |
| B．belonged to India |
| C．was one of the British colonies |
| D．was a small island in the Pacific Ocean |
The mistake on the stamps was made _______.
| A．in Mauritius | B．at Mauritius Government House |
| C．in a post office | D．in London |
Stamp collectors have paid 16 800 for _______.
| A．fourteen One Penny Orange-Reds |
| B．twelve Two Penny Blues |
| C．one One Penny Orange-Red |
| D．one Two Penny Blue |
An important question about eating out is who pays for the meal. If a friend of yours asks you to have lunch with him. You may say something like this, “I’m afraid it’ll have to be some place cheap, as I have very little money.” The other person may say, “OK, I’ll meet you at McDonald’s.” This means that two agree to go Dutch, that is, each person pays for himself. He may also say, “Oh, no. I want to take you to lunch at Johnson’s”, or “I want you to try the steak(牛排) there. It’s great.” This means the person wants to pay for both of you. If you feel friendly towards this person, you can go with him and you needn’t pay for the meal. You may just say, “Thank you. That would be very nice.”
American customs about who pays for dates(约会) are much the same as in other parts of the world. In the old days, American women wanted men to pay for all the meals. But, today, a university girl or a woman in the business world will usually pay her own way during the day. If a man asks her to dinner or a dance outside the working hours, it means “come as my guest”. So as you can see, it is a polite thing to make the question clear at the very beginning. In the old days _______ often paid for all the meals.
| A．women | B．men |
| C．university students | D．businessmen |
“To go Dutch” means to _______.
| A．go to play outside | B．eat out |
| C．pay for oneself | D．go to a cheaper eating place |
“McDonald’s” here means _______.
| A．a tea house | B．a gate |
| C．an office | D．an eating place |
If you feel friendly to the person, _______.
| A．you should pay for him | B．you needn’t pay for him |
| C．you can accept his invitation | D．you can’t accept his invitation |
We’d better know who will pay for the meal _______.
| A．at the beginning | B．at the end |
| C．in the middle of the meal | D．after drinking |
The deserts of the world are not all covered with sand. Many of them have surfaces of rock or clay or small stones. They are not flat, either. They often have high hills and deep valleys. There is some plants’ life in many parts of the desert. There is little rain in the desert, but it does fall often enough for most plants.
The deserts of the world are not uninhabited(not lived by people). People also live outside oases(绿洲), but these people are not farmers. They have camels, goats, donkeys, sheep, etc. These animals can live on the desert plants and do not need much water.
The people of the desert have to move constantly from place to place, they must always look for grass or desert plants for their animals. They usually live in tents. When there is no more food for their animals, they fold up their tents, pat them on their camels and donkeys, and move to another place. In good years, when there is enough food for their animals, they trade their skins and their goats and camel hairs with the people of oases for wheat and fruit. But in bad years, when there is not enough food for their animals, the people of the desert would attack the oases people. But they are also hospitable, no man in the desert would ever refuse to give a stranger food and water.according to the passage, deserts are mostly made up of _______.
| A．clay | B．rock |
| C．sand | D．stones |
The underlined word “hospitable” has the meaning of being _______.
| A．brave | B．cruel |
| C．strange | D．kind |
In the desert _______.
| A．it rains in spring only |
| B．it rains for a short time every month |
| C．there is some rain, but far from enough |
| D．the rainfall is just enough for the plants |
People live _______.
| A．only inside the oases | B．only outside the oases |
| C．both inside and outside the oases | D．in places with regular rainfalls |
From the passage we know that life _______.
| A．is hard in deserts | B．is happy in deserts |
| C．is impossible in deserts | D．in deserts in much better now |
Some scientists warn that ice near the Earth’s Poles may indeed be melting. This “polar meltdown” may be the first sign that the Earth is heating up. We could be in very serious trouble if this trend continues. It is estimated that a meltdown of as little as 10 percent of Antarctica’s ice would raise sea levels around the globe by 4 to 9 meters. Floods would cover low-lying regions and turn coastal cities like New York and New Orleans into real life underwater world.
Scientists first predicted in the 1970s that heat trapped in the Earth’s atmosphere could cause a polar meltdown. Many now believe that human activities are turning up the heat. When we burn fossil fuels like coal and oil, we add carbon dioxide(CO2) gas to the Earth’s atmosphere. Cutting down trees also makes CO2 levels raise because trees normally soak up CO2 to make food. Scientists say higher CO2 levels strengthen the “greenhouse effect” and could increase the Earth’s temperature. In fact, CO2 levels have risen by 30 percent since the Industrial Revolution of the 18th and 19th centuries.
Over the past three years, satellite measurements have shown a sea level rise of about a quarter inch worldwide. “If nothing is done to reduce fossil-fuel pollution and global warming, sea levels will rise even more.” says geologist Richard Alley.
But even Alley admits that a polar meltdown would take time. The ice in Antarctica and Arctic locks up nearly nine times the volume of water contained in all the world’s rivers and lakes. These are such big “ice cubes” and it would probably take thousands of years to melt them.
Another scientist Charles Bentley doesn’t think a meltdown will happen at all. “Even if warmer temperatures begin to melt polar-ice,” he says, “the excess moisture would most likely be redeposit as snow.” In other words, the melted ice would evaporate into the atmosphere, refreeze, and fall as rain and snow over the Poles.What consequence of global warming is mentioned in the passage?
| A．More tropical storms. | B．More tropical diseases. |
| C．Changes in farm productivity. | D．Coastal flooding. |
Which of the following statements does the second paragraph support?
| A．CO2 in the atmosphere cannot keep the heat from escaping into space. |
| B．The increase of CO2 gas may warm the planet and help to melt polar ice. |
| C．Cutting down trees helps to greatly reduce CO2 levels. |
| D．The end of the short-lived age of fossil fuels is already in sight. |
Geologist Richard Alley most likely agrees that _______.
| A．the sea-level rise can be prevented by cutting back on energy-consuming activities |
| B．the recent breaking off of ice blocks from Antarctica is just a natural part of a long-term cycle |
| C．Antarctica temperatures have significantly changed since the Industrial Revolution |
| D．the polar meltdown may be an accidental change of climate rather than a sign of global warming |
Charles Bentley believes that a polar meltdown will not occur because _______.
| A．governments around the world are beginning to reduce CO2 levels in the air |
| B．a melting of the polar ice cannot be achieved with the present technologies |
| C．the melted ice in the polar areas would change into snow and rain over the Poles |
| D．the sun’s heat would have no chance of being absorbed by the polar ice |
In which paragraph does the author mention the immense quantities of polar ice?
| A．In the second paragraph. | B．In the third paragraph. |
| C．In the fourth paragraph. | D．In the fifth paragraph. |