When we look at Earth from space, we see a blue, watery world. It is no coincidence that three quarters of the surface is covered by oceans. Water is very common in the universe and is essential for lives. But life needs water in the form of liquid, not ice, and not vapor and that is a little bit less common.
For a planet to have liquid water at its surface, three things are important. First, the planet needs to be large enough that the force of gravity keeps the water molecules （分子）from flying off into space. For example, Mars is smaller than Earth, so it has less gravity, and that is one important reason that Mars has a very thin atmosphere. Second, the planet needs to have an atmosphere. Without an atmosphere, the planet is in a vacuum （真空）,and liquid water isn't stable in a vacuum. For example, our moon has no atmosphere, so if you spill some water on the moon, it will either boil away as vapor, or freeze solid to make ice. Third, the planet needs to be at the right distance from its star.
If you were an alien astronomer, you'd think Venus is a pretty good bet for life. It is the right size. It has an atmosphere and it is in the habitable zone of our sun. But Venus is not habitable, at least not at its surface. It is too hot, because Venus' atmosphere is full of carbon dioxide, an important greenhouse gas. In fact, its atmosphere is almost entirely carbon dioxide, and almost 100 times thicker than our own. As a result, the temperature on Venus is hot enough to melt lead, and the planet is dry as a bone.
So finding a suitable planet for humans to live on is only a beginning. Don't expect much.
1. What do we know about water from the text?| A．Water has two forms. |
| B．Water is a necessity for humans. |
| C．It is common to see liquid water on the moon. |
| D．Water flies into space easily with the help of gravity. |
| A．It is very hot | B．It has no atmosphere |
| C．It is far from the Sun | D．It is smaller than Earth |
| A．Positive. | B．Passive. |
| C．Hopeful. | D．Desperate. |
| A．Water changes its forms. |
| B．A living problem on Venus. |
| C．The research of an alien astronomer. |
| D．Conditions for a habitable globe for humans. |
相似题推荐
【推荐1】Would you like to spend a year pretending to live on Mars in a 1,700-square-foot space shared with three other people? If that's your idea of a dream job, you can thank your lucky stars, because NASA is hiring.
The agency is seeking applicants for what it calls a “one-year mission in a habitat to simulate (模拟）life on a distant world. "NASA plans to observe humans in a Mars-like situation on Earth so it can study the challenges that might occur during a future mission to the red planet.
Grace Douglas, the lead scientist for NASA's Advanced Food Technology research effort at NASA's Johnson Space Center in Houston, says the simulated mission will benefit future missions that actually go to space. “Simulations on Earth will help us understand and counter the physical and mental challenges astronauts will face before they go.” Douglas says.
NASA is looking for four crew members who will live and work for a year in a 3D-printed, 1,700-square-foot module called Mars Dune Alpha, based at NASA's Johnson Space Center. According to NASA, the crew might perform tasks such as simulated spacewalks, using virtual reality and robotic controls, exchanging communications and conducting other studies.
The posting calls for healthy and motivated U.S. citizens between the ages of 30 and 55 years old, plus a STEM master's degree or sufficient experience piloting an aircraft.
It won't necessarily be an easy task, though. NASA warns that the crew will experience simulated problems like those humans might face on Mars, including resource limitations, equipment failure, communication delays and other environmental stressors.
In exchange, selected crew members will help bring humans one step closer to reaching Mars.
1. What can we learn from the passage?| A．Three more astronauts are needed. |
| B．The one-year mission is far from easy. |
| C．Whoever is crazy about space will get an offer. |
| D．A STEM master's degree is a must for application. |
| A．To test how their aircraft works. |
| B．To work as astronauts on Mars. |
| C．To observe human reactions on Mars. |
| D．To experiment with possible challenges on Mars. |
| A．Life of the Four Applicants on Mars |
| B．Applicants Wanted for the Future on Mars |
| C．The Obstacles Candidates Will Face on Mars |
| D．The Great Significance of Space Technology |
【推荐2】A newly discovered planet looks just right for life as we know it, according to an international group of astronomers. Orbiting a star about 500 light-years away, the planet called Kepler-186f is about the same size as Earth. It orbits its star at the right distance for liquid water on the surface. That is a necessary condition for life as we know it.
But it is not exactly like Earth, NASA planetary scientist Elisa Quintana said. "It's more of an Earth's cousin. It's not an Earth's twin. It shares the same characteristics as Earth, but their parent stars are very different," said Quintana.
Kepler-186f orbits a star that is smaller and cooler than our sun. But, writing in the journal Science, the astronomers say the planet appears to be a closer relative than most of the hundreds of others discovered so far. Some are massive gas-covered giants with thick, crushing atmospheres. Others orbit too close to their stars and are too hot for life.
Two planets discovered last year are in the right orbit and might be good candidates for life, Quintana says, but they are a bit bigger than Earth. "For the first time, we can actually say we now have a planet that is both Earth-sized and orbits in its star's habitable zone," she said.
It may be the first time, but it probably is not the last, says Massachusetts Institute of Technology astrophysicist Sara Seager. "We've been waiting decades to understand how common habitable planets might be, and it's looking like they're really common. And this gives us excitement and motivation to take the next step," said Seager.
The next step would be to look for signs of life in the atmospheres of these distant worlds. That would take a more sophisticated (高端的；复杂的) space telescope. But budget cuts threaten that mission, says University of California at Los Angeles astrophysicist Ben Zuckerman, "In principle, we could do this in the next few decades. But in practice, because there's no money, it's not gonna happen. It's not gonna happen in my lifetime, for example."
Leaving earthbound concerns behind, NASA's Elisa Quintana believes that when the next-generation space telescope is launched, it will find that we are not alone in the universe.
1. What does the underlined word "That" (Paragraph 1) refer to________| A．The right distance. | B．Liquid water. |
| C．The right size. | D．A star. |
| A．is more of an Earth's cousin than an Earth's twin |
| B．has a lot in common with Earth, including their parent stars |
| C．is a lot bigger than Earth |
| D．is smaller and cooler than our sun |
| A．Where there is water, there is life |
| B．A planet exactly like Earth found |
| C．Life discovered on Kepler-186f |
| D．New Earth-size planet found |
【推荐3】Driving to a friend’s house on a recent evening,I was attracted by the sight of the full moon rising just above my friend’s rooftops.I stopped to watch it for a few moments,thinking about what a pity it was that most city people,myself included,usually miss sights like this because we spend most of our lives indoors.
My friend had also seen it.He grew up living in a forest in Europe,and the moon meant a lot to him then.It had touched much of his life.
I know the feeling.Last December I took my seven-year-old daughter to the mountainous jungle of northern India with some friends.We stayed in a forest rest-house with no electricity or hot water.Our group had campfires outside every night,and indoors when it was too cold outside.The moon grew to its fullest during our trip.Between me and the high mountains lay three or four valleys.Not a light shone in them and not a sound could be heard.It was one of the quietest places I had ever known,a bottomless well of silence.And above me was the full moon,which struck me deeply.
Today our lives are filled with glass,metal,plastic and fibre-glass.We have televisions,cellphones,heaters,ovens,air-conditioners,cars and computers.
Struggling through traffic that evening at the end of a tiring day,most of it spent indoors,I thought:before long,I would like to live in a small cottage.There I will grow vegetables and read books and walk in the mountains.I may become an old man there,and wear the bottoms of my trousers rolled and measure out my life in coffee spoons.But I will be able to walk outside on a cold silent night and touch the moon.
1. The writer felt sorry for himself because .| A．there was too much pollution |
| B．he usually missed the full moon sights |
| C．he didn’t adapt to modern inventions |
| D．there were too many accidents on the road |
| A．No modern equipment. |
| B．Complete silence. |
| C．The nice full moon. |
| D．The high mountains. |
| A．show that the writer likes city life very much |
| B．tell us that people greatly benefit from modern life |
| C．explain that people have few chances to enjoy nature |
| D．show that we can also enjoy nature at home through them |
| A．Touched by the Moon |
| B．The Pleasures of Modern Life |
| C．A Bottomless Well of Silence |
| D．Break away from Modern Life |
【推荐1】There are various ways in which to read body language so that you can understand how someone is feeling. Reading emotional clues （线索）is one of them.
Crying is considered to be caused by an explosion of emotion in most cultures. Often times crying is considered a sign of sadness, but crying can also be an expression of happiness. Crying can also come about through laughter and humor. Thus, when judging crying, you'll need to look for other signs to determine the meaning of the crying. Crying can also be forced in order to gain sympathy or to cheat others. This practice is known as " crocodile tears" , an expression that draws on the wrong idea that crocodiles" cry" when catching prey（猎物）.
Signs of threat include v-shaped eye brows, wide eyes, and an open or down-turned mouth. In a similar way, arm tightly crossed over the other is a common sign that the person is angry and is closing himself off to you.
When people show anxiety, they display increased facial movements, and their mouth made into a thin line. Individuals who are anxious may also play with their hands, unable keep them in one spot. Anxiety can also or have nervous legs. It can be conveyed when people seemingly unconsciously（无意识 地）tap their feet or have nervous legs.
Embarrassment can be expressed by turning the eyes or shifting them away. If someone looks down at the floor a lot, they are probably shy, afraid, or embarrassed. People also tend to look down when they are upset, or trying to hide something emotional. People are often thinking and feeling unpleasant emotions when they are in the process of staring at the ground.
There are also some signs of pride. People show pride by displaying a small smile, holding their head backward, and putting their hands on their hips.
1. In what situation may one have"crocodile tears"?| A．When he is sad. | B．When he cheats others. |
| C．When he supports others. | D．When he is angry. |
| A．Shape his eye brows into a"w". | B．Sigh heavily. |
| C．Cross his arms tightly. | D．Open his eyes wide. |
| A．Most of them show negative feelings. | B．They usually express positive emotions. |
| C．They can be controlled well be humans. | D．They are good for people's health. |
| A．How to use body languages? | B．What are body languages? |
| C．What expressive emotions we have? | D．How to read emotional clues? |
【推荐2】Anyone who commutes（通勤）by car knows that traffic jams are an unavoidable part of life. But humans are not alone in facing potential backups.
Ants also commute-between their nest and sources of food. The survival of their colonies depends on doing this efficiently.
When humans commute, there's a point at which cars become dense（稠密）enough to slow down the flow of traffic, causing jam. Researchers wanted to know if ants on the move could also get stuck. So they regulated traffic density by constructing bridges of various widths between a colony of Argentine ants and a source of food. Then they waited and watched, trying to find out at what point they are going to have a traffic jam.
The researchers then took a closer look at how the behaviour of individual ants impacted traffic as a whole. And they found that when ants sense overcrowding, they adjust their speeds and avoid entering high-density areas, which prevents jams. These behaviors may be promoted by pheromones, chemicals that tell other ants where a trail is. The ants also manage to avoid colliding（碰撞）with each other at high densities, which could really slow them down.
Can ants help us solve our own traffic problems? Not likely. That's because when it comes to getting from point A to point B as fast as possible, human drivers put their own goals first. Individual ants have to be more cooperative in order to feed the colony. But the research could be useful in improving traffic flow for self-driving cars, which can be designed to be less like selfish humans—and more like ants.
1. How did the researchers control the traffic density of the commuting ants?| A．Through closer observation. | B．By controlling the widths of their path. |
| C．By finding out the dense points. | D．By regulating their numbers. |
| A．They depend on their natural chemicals to adjust their speeds. |
| B．They follow a special route. |
| C．They never stop or slow down on the way. |
| D．They level off at high densities. |
| A．Traffic jams | B．Survival of an ant colony. |
| C．Differences between human and ants. | D．Unavoidable? Not for ants! |
【推荐3】Animal moms are great ones. You might be surprised at some of these moms.
Octopuses (章鱼）
The mother octopus lays about 50,000 eggs. For about 300 days, she stays with the eggs, cleans them and protects them. She does not leave to feed. However, this animal mom dies as soon as the eggs are hatched (孵化）.
Crocodiles
A crocodile mother puts a lot of time and effort into raising her babies. She starts by building a nest, which she guards for over two months! When the eggs are ready to hatch, the young crocos call out to their mother, who digs them out and helps them hatch. She then in her mouth down to the water, where she will guard them for several more weeks or months until they learn to hunt on their own.
Bats
Bats become moms by hanging head up in a cave, giving birth. Catching the youngster before it can fall to the ground below, she puts it in a pouch (育儿袋). bat moms may carry babies with them when feeding for the first few days. As the little bats get bigger and heavier, moms help them hang on the wall of their caves and return often to feed them. It continues for about three weeks, until the babies are grown up and able to fly on their own.
Koalas
The animal mom gives birth after a pregnancy of only 35 days. The hairless baby climbs into its mother’s pouch and lives there for another five months. When the little koala is between five and eight months old, it leaves the pouch for short periods of time but returns for safety. Once it is too big to return to the pouch, it will climb onto its mother’s back and ride there until it is about 12 months old.
1. Which animal moms die when their babies are born?| A．Octopuses | B．Crocodiles |
| C．Bats | D．Koalas |
| A．gives birth by lying in the nest |
| B．gives birth by hanging in a cave |
| C．leaves its babies in the pouch for months |
| D．lets its babies live on their own after birth |
| A．35 days | B．5 months |
| C．8 months | D．12 months |
【推荐1】Animals grow up in different ways. Some newborn animals are helpless, but their mothers protect them. A newborn kangaroo is very small. It is only a few centimeters (cm) long. It closes its eyes and doesn’t have hair. It stays safe in its mother’s pouch (育儿袋) for a long time. A newborn monkey cannot walk. Its mother carries it everywhere.
Other baby animals can walk soon after they’re born. They learn to run with their mothers when danger is near. A baby zebra can run, an hour after it is born.
Some baby animals are born in a place that is safe. Baby wolves are usually born in big holes with little light. Other baby animals are born in the open. A baby elephant is often born on open land.
Animals that drink their mothers’milk are called mammals. A mother bear’s milk is rich. Baby bears have milk for a few months. This is the same as baby zebras. As baby animals grow, they need solid (固体的) food. Baby lions eat what their mother can catch!
1. According to the passage, many newborn animals need their mothers’help because the babies can’t _________.| A．look after themselves | B．eat any food |
| C．walk by themselves | D．drink water |
| A．it is very small | B．it can’t walk |
| C．it closes its eyes | D．it is very weak. |
| A．open | B．bright | C．safe | D．dry |
| A．mothers’milk | B．solid food | C．smaller animals | D．water |
| A．Six. | B．Seven. | C．Eight. | D．Nine. |
【推荐2】Life in the future will be different from the life today. Between then and now many changes will happen. But what will the changes be?
The population is growing fast. And most of them will live longer than people now.
Computers will be much smaller and more useful, and there will be at least one in every room. And computer studies will be one of the important subjects in schools then. People will work fewer hours than they do now and they will have more free time for sports, watching TV and travel. Travelling will be much cheaper and easier. And many more people will go to other countries for holidays.
There will be changes in our food, too. More land will be used for building new towns and houses for all the people. Then there will be less room for cows and sheep, so meat will be more expensive. Maybe no one will eat it every day. Instead they will eat more fruits and vegetables. Maybe people will be healthier. Work in the future will be different, too. Robots will do dangerous and hard work. Because of this, many people will not have enough work to do. This will be a big problem.
1. In the future there will be________.| A．much more fruits | B．more people | C．fewer vegetables | D．less people |
| A．work long hours | B．work fast | C．walk on foot | D．eat meat |
| A．fruit | B．fish | C．meat | D．rice |
| A．many people don’t have to work |
| B．many people will not be able to find work |
| C．people have to work fast |
| D．all the work will be done by robots |
【推荐3】People have wondered for a long time how their personalities and behaviors are formed. It’s not easy to explain why one person is intelligent and another is not, or why one is cooperative and another is competitive.
Social scientists are, of course, extremely interested in these types of questions. They want to explain why we possess certain characteristics and exhibit certain behaviors. There are no clear answers yet, but two distinct schools of thought on the matter have developed. As one might expect the two approaches are very different from one another, and there is a great deal of debate between proponents of each theory. The controversy is often (conveniently) referred to as “nature/nurture”.
Those who support the “nature” side of the conflict believe that our personalities and behavior patterns are largely determined by biological and genetic factors. That our environment has little, if anything, to do with our abilities, characteristics, and behavior is central to this theory. Taken to an extreme, this theory maintains that our behavior is predetermined to such a great degree that we are almost completely governed by our Instincts.
Proponents of the “nurture” theory, or, as they are often called behaviorists, claim that our environment is more important than our biologically based instincts in determining how we will act. Behaviorists see humans as being whose behavior is almost completely shaped by their surroundings. Their view of the human being is quite mechanistic; they maintain that like machines, humans respond to environmental stimuli as the basis of their behavior.
The social and political implications of these two theories are profound. In the United States, for example, blacks often score below whites on standardized intelligence test. This leads some “nature” proponents to conclude that blacks are genetically inferior to whites. Behaviorists, in contrast, say that the differences in scores are due to the fact that blacks are often deprived of many of the educational and other environmental advantages that white enjoy, and that, as a result, they do not develop the same responses that whites do.
Neither of these theories can yet fully explain human behavior. In fact, it is quite likely that the key to our behavior lies somewhere between these two extremes. That the controversy will continue for a long time is certain.
1. The author is mainly concerned about solving the problem ________.| A．why one’s behaviors differ from others’ |
| B．what makes different stages of intelligence |
| C．how social scientists form different theories |
| D．what causes the “nature/nurture” controversy |
| A．approaches | B．advocates | C．principles | D．characters |
| A．They believe human beings are mechanical. |
| B．They compare our behaviors to the machines. |
| C．They suggest that we react to the environment as the machines do. |
| D．They uphold that the mechanistic theory can be applied on us as well. |
| A．are the result of the educational disadvantages |
| B．have nothing to do with their true intelligence |
| C．are an indication of the blacks’ poor intelligence |
| D．have nothing to do with factors other than instincts |
【推荐1】Do you know what a castle is? A castle is a building special to Europe. Castles were built in the Middle Ages by king and other powerful people who live in. Castles were used by people to protect themselves from their enemies. They are big buildings made form stone and wood.
Today there are still castles all over Europe. Some are in ruins. But some built later are still in good repair and used even today. One example is Windsor Castle, which is a home to the British queen. It is in the country or Berkshire, not far from London.
Castles have walls around them. In the old days, soldiers would stand on the walls to guard the people in the castle. If enemies came they would shoot arrows and throw stones at them. Castles also had moats. A moat is a river around the wall that makes it difficult for enemies to get in. It could be either dry or filled with water.
Other people from younger countries love European castles. In the US there are rich people who have brought broken parts of castles to their country and rebuilt them. And some people build “replica” castles — modern copies of Castle.
You probably know the Disneyland Castle in California, US. But did you know it is based on a famous castle in Germany built by King Ludwig Ⅱof Bavaria?
1. Which of the following is TRUE about the castle?| A．It is a special American building. |
| B．It is made from stone and paper. |
| C．Only king used to live in it. |
| D．People used it to protect themselves. |
| A．a wall | B．a soldier |
| C．a river | D．a stone |
| A．there are castles only in some European countries now |
| B．in the US, there used to be castles in the Middle Ages |
| C．in the US, the people rebuilt the old castles or build the modern ones |
| D．the Disneyland castle is built in Germany |
| A．The history of Windsor castles. | B．Facts about castles. |
| C．The king and the castles. | D．How to build castles. |
【推荐2】Many college students want to look for seasonal, short-term or part-time jobs to get extra cash, to stay busy or to get working experience.
Lifeguard
The job is a great opportunity to build your fitness, keep people safe and be outdoors to enjoy some fun on the beach in the sun. The average hourly wage for lifeguards is $9.31, but those with certifications or previous experience may be able to earn a bit more.
Nanny (保姆)
Students can find plenty of positions as parents rush to arrange activities and find care for their children. Students who enjoy spending time with kids, staying active and being outdoors can spend their spare time making money without even feeling like they’re working. Nannies make $14.56 per hour on average.
Camp Consultant
Students who enjoy spending their time with children, being a leader and monitoring fun outdoor activities are perfect for camp consultant positions. The average hourly wage for camp consultants is $9.28, but those with many years’ experience or specific academic backgrounds may be able to earn more.
Food Server
Although it may not seem like the most attractive way to spend a weekend, working as wait staff allows students to build up their social skills, stay active, enjoy free meals at work and educate themselves about different cuisines. However, food servers need to be on their feet for hours at a time, so take this into account before submitting an application. The average salary is $9.00 hourly, but tips can raise that number.
1. Who are fit for the two jobs of nanny and camp consultant?| A．Students fond of camping. |
| B．Students interested in traveling. |
| C．Students enjoying staying with children. |
| D．Students eager to develop their social skills. |
| A．The way of cooking. | B．Long standing time at work. |
| C．The food you can enjoy. | D．Skill in getting tips from customers. |
| A．A lifeguard. | B．A nanny. | C．A camp consultant. | D．A food server. |
The Silk Road was not a simple trading network. It passed through thousands of citied and towns. It started from eastern China, across Central Asia and the Middle East, and ended in the Mediterranean Sea. It was used from about 200 B, C, to about A, D, 1300, when sea travel offered new routes(路线) , It was sometimes called the world’s longest highway. However, the Silk Road was made up of many routes, not one smooth path. They passed through what are now 18 countries. The routes crossed mountains and deserts and had many dangers of hot sun, deep snow and even battles. Only experienced traders could return safe.
The Silk Road got its name from its most prized product. Silk could be used like money to pay taxes or buy goods. But the traders carried more than just silk. Gold, silver, and glass from Europe were much found in the Middle East and Asia. Horses traded from other areas changed farming practices in China. Indian merchants traded salt and other valuable goods. Chinese merchants traded paper, which produced an immediate effect on the West. Apples traveled from central Asia to Rome. The Chinese had learned to graft(嫁接) different trees together to make new kinds of fruit. They passed this science on to others, including the Romans. The Romans used grafting to grow the apple. Trading along the Silk Road led to world-wide business 2,000 years before the World Wide Web.
The people along the Silk Road did not share just goods. They also shared their beliefs. The Silk Road provided pathways for learning, diplomacy(外交), and religion (宗教)
1. It’s probable that traders along the Silk Road needed .
| A．to remember the entire trade route | B．to know the making of products |
| C．to receive certain special training | D．to deal with a lot of difficulties |
| A．it was made up of different routes | B．silk trading became less popular |
| C．sea travel provided easier routes | D．people needed fewer foreign goods |
| A．learned from one another | B．shared each other’s beliefs |
| C．traded goods along the route | D．earned their living by traveling |
| A．The Silk Road ; Past and Present | B．The Silk Road; East Meets West |
| C．The Silk Road; Routes Full of Dangers | D．The Silk Road; Pathways for Learning |
