I give two examples as to why intelligent life may not actually exist, though I admit that for me, or even for a physicist who devoted his or her entire life to researching and studying the universe, it's shocking to claim that completely no life exists elsewhere.
Keeping that in mind, I'd just like to consider conditions elsewhere in the known universe. You really only need to look at our own solar system or the Earth at certain periods in its own history to appreciate that most places are much worse and much less suitable for life than our mild, watery globe.
So far, space scientists have discovered about seventy planets outside the solar. But it appears that if you wish to have a planet suitable for life, you just have to be very lucky, and the more advanced the life is, the luckier you'll have to be. I'm by no means a space observer, but I can recognize some particularly fortunate breaks we've had on the Earth. For example:
We are, to a degree, at the right distance from the perfect type of star, the one that is big enough to radiate a huge amount of energy, but not so big as to bum itself out quickly. Had our sun been ten times as huge, it would have burnt out completely after only ten million years, instead of ten billion and surely we would not exist. Too near, everything on the Earth would have boiled and withered away; any further, everything would have frozen over.
The universe is a surprising place, and our existence within it is a wonder. If a long and unimaginably complex sequence of events dating back 4.6 billion years or so hadn't happened in a particular manner at a particular time --if, to take just one example, the dinosaurs hadn't been wiped out by a meteor(流星)--we might still be a few centimeters long, with whisker(胡须) and a tail, and you'll be reading this in a cave somewhere.What's the best title for this passage?
| A．No Life Exists out of the Earth |
| B．Seventy Planets Discovered |
| C．A Place Full of Wonders |
| D．Perfect Conditions for Life |
What makes the Earth more suitable for life than other planets in the solar system?
| A．The Earth is the only planet that can receive energy from the sun. |
| B．The sun is at the right distance from us and in proper size. |
| C．The distance between the planets was neither too long nor too near. |
| D．The dinosaurs were no longer a threat to the Earth. |
What does the underlined phrase "withered away" in the 4th paragraph mean?
| A．Exploded. | B．Expanded. | C．Floated away. | D．Dried and died. |
Where does the text probably come from?
| A．A history book. | B．A magazine. | C．A science fiction. | D．A famous novel. |
Chicken feathers are useful, and not just to a chicken. Some go into pillows, coats and other products. But countless chicken feathers go to waste.
In the United States, billions of chickens are produced yearly. Most of their feathers are thrown away.
But instead of being buried in land, some feathers could find a future in plastics（塑料）.
One of the products they have developed is a flowerpot（花盆）. It may look like other flowerpots. But the container breaks down in the earth within one to five years. And as it breaks down, it naturally becomes nutrient（营养物） in the soil.
The environmentally friendly flowerpot is the work of two researchers. Walter Schmidt is with the Agricultural Research Service, part of the United States Agriculture Department. Masud Huda is with the Horticultural Research Institute, a private（私人） organization（组织）.
Walter Schmidt has been working to find uses for chicken feathers since the 1990s. Progress in 2002 showed that plastic made from feathers could be formed like other plastics.
He says feathers are much stronger and last（持续） longer than another plant material. "Feathers are stronger. By design, feathers are also more durable（耐用的）. And the other part about it is if feathers were twice as heavy, or half as strong, then birds couldn't fly."
He points out that traditional flowerpots made from other plastics can last much longer. But he wonders if there is really a need. He says most flowerpots are never re-used.
"Why would you want a plastic that you use for a year to last for two hundred years? It makes no sense. You want to match the product with the use." said Walter Schmidt.
Walter Schmidt and Masud Huda are now adding another chicken product to their flowerpots -- chicken waste. The waste will add more nutrients to the soil as the pot breaks down. The scientists say they hope their flowerpot will be on the market in a year or two.What do people mainly deal with feathers?
| A．Feathers are used to make pillows, coats and other products. |
| B．Most feathers are paid no attention to. |
| C．Most feathers are used as nutrient |
| D．Most feathers are used to make flowerpots |
What’s the advantage of the flowerpots?
| A．They won’t last long. | B．They can’t break |
| C．They are environmentally friendly | D．They can be reused |
What does Walter Schmidt think of traditional flowerpots?
| A．Too heavy | B．Too old |
| C．Never re-used | D．lasting longer but unnecessary |
What do you think is the main idea of the passage?
| A．Chicken and its feathers | B．How to deal with feathers |
| C．feathers made into flowerpot | D．New flowerpots |
Experts say the temperature in Eyjafjallajokull's hole appears to have fallen to 100C, meaning it is now producing steam, not magma（岩浆）.
But officials warned that it was too early to say whether the eruption was over completely.
Ash clouds from the volcano grounded thousands of flights last month.
Steinunn Jakobsdottir, a geophysicist from the Icelandic Meteorological Office, told the BBC that the volcano was "kind of not active for the moment".
"The history of the volcano is such that it calms down and then it gets energy again," she said.
"There are still earthquakes under the volcano, and the small earthquake is still not quite down to what it was before the eruption."
'Difficult to say'
Magnus Gudmundsson, of Iceland University, flew over the volcano on Sunday and said information from heat cameras showed the temperatures at the crater had fallen below 100C.
But he told the AFP news agency that nothing was promised and that the previous eruption at the volcano had lasted 13 months, from 1821-23.
"It stopped and started again several times with different intervals（间隔）, so it's difficult to say, difficult to give a timeline," he said.
He also said it was impossible to say whether the neighbouring Katla volcano - a much larger mountain - might also erupt.
At the height of its activity, the volcano sent out huge clouds of ash, which led to airlines grounding their planes for fear it could interfere with plane engines.
It was the biggest action of closing airspace in Europe since World War II, and affected at least 10 million passengers worldwide.What do expert think Eyjafjallajokull is like now?
| A．Magma is still coming out |
| B．The hole appears about 100 degrees C |
| C．The eruption was not over |
| D．It is very cold. |
How do expects know the temperature in Eyjafjallajokull's hole?
| A．By taking photos | B．By taking its temperature |
| C．By going close to it | D．By driving past it |
What does Steinunn Jakobsdottir think of Eyjafjallajokull?
| A．It will erupt again soon |
| B．It will be sleeping |
| C．Another mountain might also erupt |
| D．It’s uncertain |
What do you think the main idea is?
| A．the biggest action of closing airspace in Europe |
| B．the temperature in Eyjafjallajokull's hole |
| C．The Eyjafjallajokull volcano in Iceland |
| D．The earthquake in Iceland |
根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。
1________
Examinations are almost always stressful Students rarely know exactly what to expect on the test, and those who suffer from exam fear or exam anxiety can see their grades suffer as a result of this stress. For some students，exam fear causes them to “ seize up ’’ and forget what they have studied.
2______Good study habits and learning how to relax can help students overcome exam fear.
3 ______According to Penn State University and Kids Health，proper study habits and preparation are the keys to cutting out exam fear. Avoid last-minute “cramming” for exams and actively listen while in class.
Focus on positive thoughts, relax the night before your test and reward yourself after the test is over. Often, people who suffer from exam anxiety cannot shut out negative thoughts or emotions about the test, and this can contribute to feeling more anxiety than normal 4______
Keep your mind and body healthy by getting enough sleep, eating well and exercising. Healthier people who are well-rested often do better on exams.
5_____ Exam fear is normal When that anxiety severely interferes (干扰)with your ability to take the test, however, outside help might be needed. Ask your teachers and family for support and help.
| A．How To Succeed hi An Exam |
| B．How To Overcome Exam Fear |
| C．Develop good study habits. |
| D．Understand that you are not alone and ask for help if necessary. |
E. Remind yourself that it’s just one test and that you can get through it
F. Battling this type of performance anxiety can be hard, but it is not impossible.
G. Remind yourself to read the instructions carefully.
Deception (骗术）is something that people do all the time ,and it plays an important role in military (军事的)strategy. Now some researchers are trying to figure out how to get robots to do it, by looking at the behavior of squirrels and birds.
At Georgia Tech, a team led by Ronald Arkin , a professor at the School of interactive Computing, studied the literature on squirrels hiding their acorns (橡果）.Squirrels will hide their food m a certain place, but when they see other squirrels trying to steal from them, they attempt to fool the thieves by running to a fake location.
Ronald Arkin and his Ph. D. student Jaeeun Shim used that as a model for robot behavior. They programmed the robot into tricking a “predator (捕食者）” machine by doing what εi squirrel does： showing the enemy a false location for an important resource.
The team also looked at how other animals in this case，a species of bird called Arabian babbler~ drive off predators. A babbler will make an alarm call when they see a predator and other babblers will join the bird and make more calls. They then surround the predator, all the while flapping (拍打）wings and making noises. The babblers don’t ever actually fight the animal they want to drive off； they just make enough noises and flaps around enough so that it seems that attacking a babbler isn’t worth it
They found that the deception works when the group reaches a certain size—essentially, when enough birds arrive to convince the enemy that it’s best to back off . Davis modeled that behavior in software using a military scene and found that it worked even if the group didn’t have the firepower to confront the enemy directly.
The military is interested in this because a robot that can fool an opponent is a valuable tool. It could lead an enemy down a fake trail or make itself look more dangerous than it actually is.Why does the military want to take advantage of squirrels’trick?
| A．It can reduce the use of firepower to confront the enemy. |
| B．It can fool the enemy into believing it is more dangerous. |
| C．It can lead the enemy in a wrong direction to avoid losing resources. |
| D．It can scare the enemy away who wants to destroy the acorns. |
Which of the following is NOT the way Arabian babblers drive off predators?
| A．One bird makes an alarm call and other birds will join it |
| B．They fight the enemy bravely face to face. |
| C．They make noises and flaps around the predator. |
| D．They force the predator aware that it isn't worthwhile to attack. |
What is the main idea of the passage?
| A．Animals' behaviors are researched to be applied to the study of military robots. |
| B．Robots, fooling tricks are applied to the study of animals’behaviors. |
| C．Birds and squirrels are the animals that are good at deception. |
| D．Researchers are interested m animals’military-related behaviors. |
UGG boots have been a winter-weather fashion for several years now, combining function, comfort, warmth and even some style. What many UGG-enthusiasts don’t know is that their boots are a breeding ground for bacteria and cause foot problems.
Doctors believe the boots, which are particularly popular among young teenage girls, are leading to a rise in the number of people suffering pains in their feet and knees.
Dr. Ian Drysdale，head of the British College of Osteopathic Medicine，believes because the foot does not get the proper support on the inside，it will lead to more ankle，knee，hip and back problems. “These boots are not designed for outside wear. Just because something becomes a trend or fashionable doesn’t mean it’s good or right，” he said, “The particular problem with this type of footwear is that it is unsupported. It’s a slipper. You wouldn’t normally expect to be doing outdoor activities from something that’s indoor. If you decide to wear your pajamas outside all. the time, someone will come up and say it’s not a good idea. ” Dr. Drysdale explained that the feet issues become a particular problem among young teenage girls，whose bones are “ plastic ” and developing when they are growing. “ If that structure is developing in an inappropriate way,” he said, “then the ultimate structure will be deformed ”
Mike 0，NeiU, a consultant surgeon, said, “As the foot slides around, you get wear and tear (磨损）on the joints on the inside of the foot The ankle is m the wrong position, the thigh bone also changes position, and you get an abnormal movement in the pelvis, which leads to back problems. ”
UGG AustraUa9 who makes the designer version of the boots, told The Daily Mirror that their boots are “comfort” rather than “performance” footwear and consumers should be aware of “knockoffs”（仿制品)which lack reinforced heels in their boots.Teenage girls prefer to wear UGG boots because of the following except______
| A．design | B．comfort | C．quality | D．warmth |
Accordi^ to Dr. Ian Drysdale，_____
| A．there is a possibility that bacteria will multiply in UGG boots |
| B．wearing UGG boots will lead to more ankle and toe problems |
| C．it’s not a good idea to wear boots like UGG outside all the time |
| D．teenage girl’s bones are plastic enough to wear UGG boots |
The underlined word “ deformed” is closest in meaning to_____
A. shaped B_ strengthened C. reformed D. damagedWhich of the following can be the best title for the text?
| A．Potential Harm of UGG Boots | B．The Popularity of UGG Boots |
| C．The Unique Design of UGG Boots | D．Benefits of UGG Boots |
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