1 . Modern medicine’s ability to keep us alive makes it tempting to think human evolution may have stopped. But if we look at the rate of our DNA’s evolution, we can see that human evolution hasn’t stopped – it may even be happening faster than before.
Evolution is a gradual change to the DNA of a species over many generations. It can occur by natural selection, when certain traits created by genetic changes help an organism survive or reproduce. Such genes are thus more likely to be passed on to the next generation, so they increase in frequency in a population. Gradually, these changes and their associated traits become more common among the whole group.
By looking at global studies of our DNA, we can see evidence that natural selection has recently made changes and continues to do so. Though modern healthcare disrupts a key driving force of evolution by keeping some people alive longer, in countries without access to good healthcare, populations are continuing to evolve. Survivors of infectious disease outbreaks drive natural selection by giving their genetic resistance to offspring. Our DNA shows evidence for recent selection for resistance of killer diseases like Lassa fever and malaria. Selection in response to malaria remains in regions where the disease remains common.
Humans are also adapting to their environment. Gene change allowing humans to live at high altitudes have become more common in populations in Tibet, Ethiopia, and the Andes. The spread of genetic changes in Tibet is possibly the fastest evolutionary change in humans, occurring over the past 3,000 years. This rapid increase in frequency of a mutated gene that increases blood oxygen content gives locals a survival advantage in higher altitudes, resulting in more surviving children.
Diet is another source for adaptations. Studies show that natural selection favoring a change allowing adults to produce lactase – the enzyme (酶) that breaks down milk sugars – is why some groups of people can digest milk. Over 80 per cent of northwest Europeans can, but in parts of East Asia, where milk is much less commonly drunk, an inability to digest lactose is the norm. Like high altitude adaptation, selection to digest milk has evolved more than once in humans and may be the strongest kind of recent selection.
Yet, despite these changes, natural selection only affects about 8 per cent of our genome. But scientists can’t explain why some genes are evolving much faster than others. We measure the speed of gene evolution by comparing human DNA with that of other species. One fast-evolving gene is human accelerated region 1 (HAR1), which is needed during brain development. A random section of human DNA is on average more than 98 per cent identical to the chimp comparator, but HAR1 is so fast evolving that it’s only around 85 per cent similar. Though scientists can see these changes are happening – and how quickly – we still don’t fully understand why fast evolution happens to some genes but not others.
1. Which of the following statements may the author agree with?| A．Evolution occurs among several people overnight. |
| B．Genes may change and some are beneficial to people’s lives. |
| C．Evolution is done when the whole population possesses a certain gene. |
| D．The changed genes leading to higher survival rates are chosen deliberately. |
| A．explains | B．causes | C．upsets | D．heals |
| A．some people can resist infectious diseases like malaria |
| B．children in Tibet tolerate living environments with thin air |
| C．northwestern Europeans digest lactose better than East Asians |
| D．the human gene HAR1 resembles that of a chimp to a lesser extent |
| A．What Is Natural Selection? |
| B．Are Humans Still Evolving? |
| C．Why Will Certain Genes Evolve? |
| D．How Do Mutated Genes Function? |
2 . One morning, when Gregor Samsa woke from troubled dreams, he found himself transformed in his bed into a horrible insect. He lay on his armor-like back, and if he lifted his head a little he could see his brown belly, slightly domed and divided by arches into stiff sections. The bedding was hardly able to cover it and seemed ready to slide off any moment. His many legs, pitifully thin compared with the size of the rest of him, waved about helplessly as he looked.
"What's happened to me?" he thought. It wasn't a dream. His room, a proper human room although a little too small, lay peacefully between its four familiar walls. A collection of textile samples lay spread out on the table—Samsa was a travelling salesman—and above it there hung a picture that he had recently cut out of an illustrated magazine and housed in a nice, gilded frame. It showed a lady fitted out with a fur hat and fur scarf who sat upright, raising a heavy fur muff (暖手筒) that covered the whole of her lower arm towards the viewer.
Gregor then turned to look out the window at the dull weather. Drops of rain could be heard hitting the window, which made him feel quite sad. "How about if I sleep a little bit longer and forget all this nonsense," he thought, but that was something he was unable to do because he was used to sleeping on his right, and in his present state couldn't get into that position. However hard he threw himself onto his right, he always rolled back to where he was. He must have tried it a hundred times, shut his eyes so that he wouldn't have to look at the floundering legs, and only stopped when he began to feel a mild, dull pain there that he had never felt before.
He thought, "What a heavy career it is that I've chosen! Travelling day in and day out. Doing business like this takes much more effort than doing your own business at home, and on top of that there's the curse of travelling, worries about making train connections, bad and irregular food, contact with different people all the time so that you can never get to know anyone or become friendly with them." He felt a slight itch up on his belly; pushed himself slowly up on his back towards the headboard so that he could lift his head better; found where the itch was, and saw that it was covered with lots of little white spots which he didn't know what to make of; and when he tried to feel the place with one of his legs he drew it quickly back because as soon as he touched it he was overcome by a cold tremble.
He slid back into his former position. "Getting up early all the time," he thought, "it makes you stupid. You've got to get enough sleep. Other travelling salesmen live a life of luxury. For instance, whenever I go back to the guest house during the morning to copy out the contract, these gentlemen are always still sitting there eating their breakfasts. I ought to just try that with my boss; I'd get kicked out on the spot. But who knows, maybe that would be the best thing for me. If I didn't have my parents to think about I'd have given in my notice a long time ago, I'd have gone up to the boss and told him just what I think, tell him everything I would, let him know just what I feel. He'd fall right off his desk! And it's a funny sort of business to be sitting up there at your desk, talking down at your inferiors from up there, especially when you have to go right up close because the boss is hard of hearing. Well, there's still some hope; once I've got the money together to pay off my parents' debt to him—another five or six years I suppose—that's definitely what I'll do. That's when I'll make the big change. First of all though, I've got to get up, my train leaves at five."
1. According to the passage, Gregor initially believes his transformation is a ?| A．curse | B．disease | C．nightmare | D．fraud |
| A．struggling | B．painful | C．pitiful | D．trembling |
| A．remind the reader that Gregor has already turned into an insect |
| B．stress the disconnection between Gregors' thoughts and his actual situation |
| C．present important details about what Gregor's new body looks like |
| D．show that Gregor's thoughts are focused on the changes to his body |
| A．provide a solution to the conflict Gregor faces |
| B．foretell the conflict between Gregor and his boss |
| C．illustrate Gregor's flexibility and ability to move on |
| D．emphasize Gregor's extreme sense of duty |
3 . Exciting concertos（协奏曲）from Vivaldi’s The Four Seasons can boost mental alertness, according to research from North-umbria University. The findings, which are published in Experimental Psychology, show that the exciting first movement（乐章）, in particular, is capable of enhancing attention and memory.
In the experiment a group of 14 young adults were given a mental concentration task to perform. They were asked to press the space bar on a keyboard when a green square appeared on screen and ignore different colored circles and squares that appeared at intervals. The participants carried out this task both in silence and while listening to each of the four concertos while their brain activity was measured using EEG（脑电图扫描）brain imaging.
Results showed that participants responded correctly faster when listening to the exciting Spring concerto. When listening to the concerto, the average response time in performing the task was 393.8 milliseconds（毫秒）as opposed to 408.1 milliseconds when the task was carried out in silence. This response time rose to 413.3 milliseconds when they listened to the slower and sadder Autumn music, therefore showing a decrease in mental capacity.
Psychologist Dr. Leigh Riby said, “The Spring movement enhanced overall activity within the brain but had an exaggerated effect on the area of the brain that’s important for emotional processing. It seemed to give rise to particular imagery in the brain and evoke positive, contented feelings which translated into higher levels of cognitive functioning.”
Dr. Riby suggests that the Spring movement is particularly special and be used in therapy and is, in fact, quite a familiar piece to most people as it has been used successfully in marketing to induce mood and influence behavior. He also found that the key in which the music was written had no impact on brain performance. While the Spring concerto, which is written in a major key, did not. He added, “This experiment shows that cognitive capacity is enhanced when pleasant and arousing stimuli are introduced.”
1. What do we know about the research from Northumbria University?| A．It was conducted in four different seasons of a year. |
| B．It showed sad and slow music can boost mental alertness. |
| C．The results of the research have been published. |
| D．It was done by a group of 14 young adults. |
| A．When they were in complete silence. |
| B．When they were listening to slow and sad music. |
| C．When they were listening to the Autumn concerto. |
| D．When they were listening to the Spring concerto. |
| A．arouse | B．command |
| C．require | D．deserve |
| A．an official document | B．a science journal |
| C．a society section of a newspaper | D．a guidebook |
4 . HOW TO GET THERE
BA and Royal Jordanian airlines fly direct between London Heathrow and Jordan’s capital city Amman (from £435; rj. com). Flight time is five hours.
HOW TO GET AROUND
Jordan is a joyfully easy country to travel around, in part due to its small size. You could drive from top to bottom in little over five hours if you wanted to. The national bus company has services between the main towns, and limited options to Petra and the Dead Sea. For full flexibility, you're better off hiring a car—roads are in good condition, and other drivers tend to be less manic (not stand up to free use of the car horn) compared to other countries in the Middle East. The traffic in Amman makes it frustrating, and nerve-wracking, to navigate, so pick up and drop off your car at the airport, a little outside of the city. The usual suspects have offices there (week’s hire from £235; hertz. jo).
HOW LONG TO SPEND
Given the short travel times between major sites, you could feasibly whip around Jordan in little under a week, spending a night in each location. However, it’s important to factor in the weather: your pace will slow in high temperatures, and you’ll find many Jordanians sensibly spending the hottest part of the day indoors, indulging in a long lunch. You’ll also want to devote a proper amount of time to each location: two or three nights in each of Petra and Wadi Rum will allow you to get to a few less explored corners, while two nights in Amman and one each at the Dead Sea and hot springs is about right. If you add in a side trip for some diving in the Red Sea, two weeks is plenty.
WHAT TO BUDGET
Staying in budget guesthouses, eating only from markets and street stalls, and using public transport, you could survive in Jordan on around £40 per day. Factor in a midrange hotel, car hire, guided tours and meals in local restaurants, and the figure could rise to £100-plus a day. The national currency is the dinar（第纳尔）, and is available from ATMs at all the main sites.
WHEN TO GO
High season is September to October and March to May, when the weather is warm but bearable. Note that price hikes are common in this period, and hotels get booked far in advance. One of the most pleasant times to visit is winter, from November to February, though be aware the desert gets very cold at night during this period. If you can take the extreme temperatures of summer, it can be an excellent time to travel, with fewer tourists around.
HOW TO PLAN
See Lonely Planet’s Jordan and the Jordan tourist board’s official site, visitjordan.com, which has a wealth of information on general travel in the region and specific sites.
1. Which of the following statements is True about travelling in Jordan according to the passage?| A．Drivers in Jordan use car horn more freely than those in other countries. |
| B．It's better to drive your own car since the traffic in Amman is frustrating. |
| C．Weather should be taken into consideration when you arrange holiday. |
| D．Diving in Red Sea is a must if you plan to travel in Jordan for one week. |
| A．To choose what kind hotels. |
| B．To eat what kind of food. |
| C．Whether to use cash or not. |
| D．When to travel in Jordan. |
| A．declines | B．rises | C．varies | D．collapses |
5 . Two things changed my life: my mother and a white plastic bike basket. I have thought long and hard about it and it’s true. I would be a different person if my mom hadn’t turned a silly bicycle accessory into a life lesson I carry with me today.
My mother and father were united in their way of raising children, but it mostly fell to my mother to actually carry it out. Looking back, I honestly don’t know how she did it. Managing the family budget must have been a very hard task., but she made it look effortless. If we complained about not having what another kid did, we’d hear something like, “I don’t care what so-and-so got for his birthday, you are not getting a TV in your room/a car for your birthday a lavish sweet-16 party.” We had to earn our allowance by doing chores around the house. I can still remember how long it took to polish the legs of our coffee table. My brothers can no doubt remember hours spent cleaning the house. Like the two little girls growing up at the White House,we made our own beds (no one left the house until that was done) and picked up after ourselves. We had to keep track of our belongings, and if something was lost, it was not replaced.
It was summer and, one day, my mother drove me to the bike shop to get a tire fixed -- and there it was in the window. White, shiny, plastic and decorated with flowers, the basket winked at me and I knew -- I knew-- I had to have it.
“It’s beautiful,” my mother said when I pointed it out to her, “What a neat basket.”
I tried to hold off at first, I played it cool for a short while. But then I guess I couldn’t stand it any longer: “Mon, please can I please, please get it? I’ll do extra chores for as long as you say, I’ll do anything, but I need that basket, I love that basket. Please, Mom .Please?”
I was desperate.
“You know,” she said, gently rubbing my back while we both stared at what I believes was the coolest thing ever, “If you save up you could buy this yourself.”
“By the time I make enough it’ll be gone!”
“Maybe Roger here could hold it for you,” she smiled at Roger, the bike guy.
“He can’t hold it for that long, Mom. Someone else will buy it. Please, Mom, Please?”
“There might be another way,” she said.
And so our paying plan unfolded. My mother bought the beautiful basket and put it safely in some hiding place I couldn’t find. Each week I eagerly counted my growing saving increased by extra work here and there (washing the car, helping my mother make dinner, delivering or collecting things on my bike that already looked naked without the basket in front). And then, weeks later, I counted, re-counted and jumped for joy. Oh, happy day! I made it! I finally had the exact amount we’d agreed upon….
Days later the unthinkable happened. A neighborhood girl I’d played with millions of times appeared with the exact same basket fixed to her shiny, new bike that already had all the bells and whistles. I rode hard and fast home to tell my mother about this disaster. This horrible turn of events.
And then came the lesson. I’ve taken with me through my life: “Honey, your basket is extra-special,” Mom said, gently wiping away my hot tears. “Your basket is special because you paid for it yourself.”
1. What can we learn from the first two paragraphs?| A．The author came from s well-off family. |
| B．The children were fond of the US president’s daughters. |
| C．The mother raised her children in an unusual way. |
| D．The children enjoyed doing housework. |
| A．something impossible to get | B．something she could afford |
| C．something she could do without | D．something important to her |
| A．the basket cost more than she had saved |
| B．something spoiled her paying plan |
| C．someone else had got a basket of the same kind |
| D．a neighborhood girl had bought a new bike |
| A．Save money for a rainy day |
| B．Good advice is beyond all price. |
| C．God helps those who help themselves |
| D．Earn your bread with your sweat |
In an effort to prevent language loss, scholars from a number of organizations- UNESCO and National Geographic among them –have for many years been documenting dying languages and the cultures they reflect.
Mark Turin, a scientist at the Macmillan Center, Yale University, who specializes in the languages and oral traditions of the Himalayas, is following that tradition. His recently published book, A Grammar of Thangmi with an Ethnolinguistic Introduction to the Speakers and Their Culture, grows out of his experience living, looking and raising a family in a village in Nepal.
Documenting the Tangmi language and culture is just a starting point for Turin, who seeks to include other languages and oral traditions across the Himalayans reaches of India, Nepal, Bhutan, and China. But he is not content to simply record these voices before they disappear without record.
At the University of Cambridge Turin discovered a wealth of important materials- including photographs, films, tap recordings, and field notes- which had remained unstudied and were badly in need of care and protection.
Now, through the two organizations that he has founded-the Digital Himalaya Project and the World Oral Literature Project- Turin has started a campaign to make such documents, found in libraries and stores around the world, available not just to scholars but to the youngers.
Generations of communities from whom the materials were originally collected.Thanks to digital technology and the widely available Internet. Turin notes, the endangered languages can be saved and reconnected with speech communities.
1. Many scholars are making efforts to ________.
| A．promote global languages |
| B．rescue the disappearing languages |
| C．search for language communities |
| D．set up languages research organizations |
| A．Having first records of the languages. |
| B．Writing books on language searching. |
| C．Telling stories about language users. |
| D．Linking with the native speakers. |
| A．The cultural statics in India. |
| B．The documents available at Yale. |
| C．His language research in Britain. |
| D．His personal experience in Nepal. |
| A．Write sell and donate. |
| B．Record, repeat and reward. |
| C．Collect, protect and reconnect. |
| D．Design, experiment and report. |
7 . Pessimism VS. Progress
FASTER, CHEAPER, BETTER—technology is one field many people rely on to offer a vision of a brighter future. As the 2020s dawns, however, optimism is in short supply. The new technologies that have dominated the past decade seem to be making things worse. Social media was supposed to bring people together, but today, it is better known for invading privacy. Parents worry that smartphones have turned their children into screen-addicted zombies.
This depressed mood is centered on smartphones and social media, which took off a decade ago. However, concerns have arisen that particular technologies might be doing more harm than good. The 1920s witness a resistance to cars, which had earlier been seen as a miraculous answer to the problem of horse-drawn vehicles. In the 1970s, the depression was prompted by concerns about environmental damage and the prospect of nuclear accidents.
In each of these historical cases, disappointment arose from a mix of unrealized hopes and unforeseen consequences. Technology produces the forces of creative destruction, which replaces the outdated production units, so it is natural that it leads to anxiety. For any given technology, its drawbacks sometimes seem to outweigh its benefits. When this happens with several technologies at the same time, as it does today, the result is a wider sense of techno-pessimism.
However, this pessimism can be overdone. Too often people focus on the disadvantages of a new technology while taking its benefits for granted. Worries about screen time should be weighed against the instant access to information and entertainment that smartphones make possible. Efforts to avoid the short-term cost associated with a new technology will end up denying access to its long-term benefits. Fears that robots will steal people’s jobs may promote governments to tax them, for example, to discourage their use, but in the long run, countries that wish to maintain their standard of living as their workforce ages and shrinks will need more robots, not fewer.
That points to another lesson: the remedy for technology-related problems very often involves more technology. Airbags and other improvements in safety features, for example, mean that in America, deaths in car accidents per billion miles travelled have fallen from around 240 in the 1920s to around 12 today.
The most important lesson is about technology itself. Any powerful technology can be used for good or ill. Biotechnology, for example, can raise crop yields and cure diseases, but it could equally lead to deadly weapons.
Technology itself is neutral. It is the choices people make about it that shape the world. Will technology lead to pessimism or progress? The question should be settled by a broad debate, not by a small group of technologists.
1. The word “prompted” in paragraph 2 probably means _______.| A．caused | B．prevented | C．relieved | D．removed |
| A．technological innovations hardly cause unexpected problems |
| B．people assume the faults of new technologies to be natural |
| C．new technologies tend to emerge with uncertainty about future |
| D．new technologies cause more disadvantages than advantages |
| A．optimism over new technologies is in short supply as the 2020 comes |
| B．pessimism over innovations, if not overdone, is helpful and even essential |
| C．people tend to care more about innovations’ problems than about their benefits |
| D．people’s wise decision on the use of new technologies really matters |
8 . Have you ever noticed how the recital (叙说) of an adventure always finds ready audience? The man with a story of some stirring adventure always takes the floor Men will stop the most important discussion to listen. Women will forget to rock the cradle. Boys and girls will neglect any sport or game. Try it sometime and see how it grips all kinds and all ages. And the reason is that none of us ever really grows up. We are always boys and girls, a little older in years, but with the same nature—alert to the new, questioning, investigating, growing, living; stirred by martial music; thrilled by the sight of the fire-houses dashing madly down the street; lured by tales of subtle intrigue (阴谋)and splendid daring.
It would be sad if men and women ever lost this capacity to be attracted by tales of heroism. The man whose heart leaps for joy at the sight of a heroic deed is the man who will act the hero when his turn comes. No, the love of adventure will never be lost. It is a fundamental part of human nature, just as sentiment (感情) is.
So we reasoned that a magazine edited for this universal hunger of human nature for adventure ought to have a wide appreciation and appeal, and we decided to publish such a magazine and call it ADVENTURE.
It is published as a magazine wherein thousands of men and women can find adventure without being obliged to read through large amounts of stuff they care little about for the sake of getting a little they care a lot about, which is frankly made for the hours when the reader cannot work, or does not wish to, or is too weary to work and made for the reader’s recreation rather than his or her creative hours. If you care for stirring stories (and who does not?) —if you wish to get away for a brief time from the hard grind of the daily mill so that you can come back to it again with renewed passion and courage to walk through the knotty problems and nagging limitations, get a copy of Adventure.
You can get away for such a trip every month for 15 cents or you can get a season ticket entitling you to twelve trips for $1.50. No other kind of story in the magazine; just Adventure Stories. Fact-stories as well as fiction stories .If you don’t like that kind, don’t buy; but if you do like that kind, Adventure is sure to delight you.
1. Which of the following statement is TURE about man’s sense of adventure?| A．People are increasingly attracted by adventures as they grow. |
| B．The sense of adventure is rooted in a childhood curiosity. |
| C．Adventure stories are more attractive when told with sentiment. |
| D．Only children with curiosity grow into adults fond of adventures. |
| A．to draw a clear line between | B．to capture the attention of |
| C．to affect the way people think | D．to give equal treatment to |
| A．It reminds its work-burdened life driven readers of good old days. |
| B．It helps them regain their adventurous selves lost in tough life. |
| C．It offers a refreshing escape from long weary working hours. |
| D．It encourages them to face the toughness of life and work. |
| A．One can buy one copy for 15 cents. | B．Adventure is available one issue a month, |
| C．It contains fictional and true stories. | D．Season ticket holders can enjoy free tours. |
| A．To instruct publishers in how to produce a popular magazine. |
| B．To explore the psychological cause and impact of adventure. |
| C．To attract potential readers by giving the editorial philosophy. |
| D．To recommend to working people a refreshing way of recreation. |
9 . We all do it. We put off that dreaded task for five more minutes, then for thirty minutes, then for another hour, until it doesn’t get done at all. And the worst part is we still weren’t able to enjoy our day. We spend so much time stressing over that looming task that it deprives us from actually being able to focus on other tasks.
Why do we do it? We know it never ends well. The problem is that the cycle can feel nearly impossible to break. We get so caught up in the cycle of procrastination that we almost forget how to effectively tackle hard tasks.
Here are five tips for nipping procrastination in the bud and taking back control over your daily life.
Tackle the most difficult task first.
You’re probably thinking “Duh, I already knew that.” But you may not have realized that there’s scientific backing for this suggestion. We only have a limited supply of willpower. Once it’s been used up for the day, chances of us tackling hard tasks are pretty slim. Dive into your hardest task when your energy level is at its highest. This will ensure the best results.
When we push the hard tasks to the end of the day, it takes a toll on our energy all day long. In the end, stressing for hours over the task we’re procrastinating negatively affects all the other tasks on our list.
So next time you’re scheduling the items on your list, make sure to start out with worst one. It may not necessarily be the largest, but it should be the one you’re dreading the most. By accomplishing it so early in the day, you will feel energized and productive. You’ll know the rest of the day is all downhill and cruise through the list with remarkable speed.
Divide the task into smaller tasks.
We tend to get overwhelmed when a giant project looms ahead of us. We don’t know where to start or what to do first. Keep in mind that forests are made up of individual trees. Though you may not be able to take down a whole forest at once, you could certainly start with one tree (or even a branch).
If you need to organize your entire kitchen, start by working on just one cupboard. Organizing one cupboard is much more feasible than trying to get everything done in one swoop. Make a commitment to complete a small step each day, and you’ll find the task becoming less and less daunting with each new task that you accomplish.
Set a mid-day alarm.
There’s nothing more guilt-inducing than ending a day and realizing you haven’t accomplished a single task. We can avoid this rut by setting an alarm on our phone to ring every day around 1 p.m. When the ringer goes off, assess how many things on your list have been attended to.
Re-plan your schedule for the remainder of the afternoon and shift it around to take care of the most important item first. If necessary, you can indulge in a second cup of coffee to jumpstart your “second morning.” By doing this, you will avoid going to bed at night mulling over all the things you didn’t get done.
Dedicate yourself for a small period of time.
To stimulate productivity, there’s an old trick of setting a timer for ten minutes. By frantically racing the clock for that short period, you’ll likely find you become engrossed in your tasks and continue working.
The feeling of dread that has been on your mind will quickly be replaced with a sense of pride and satisfaction. Seeing what you can accomplish in ten minutes when you put your mind to it is quite motivating.
Schedule your tasks on the calendar.
Creating a game plan will help you move past the initial paralysis you feel. Instead of just writing the tasks down in a to-do list, take it a step further and identify when and how you’ll accomplish it.
For example, plan to go to the grocery store at 4:00 p.m. and start cooking dinner promptly at 4:30. By clearing up the anticipatory stress, you’ll avoid a large part of the dread that holds you back. Creating the plan is half the battle!
Though it feels impossible, you have it in you to accomplish everything that you need to every single day. With a fresh perspective, a little prodding (敦促), and a detailed plan, you’ll be well on your way to ending the procrastination cycle once and for all.
1. The word “procrastination” most likely means _______.| A．hesitation | B．delay | C．depression | D．avoidance |
| A．fully realize the importance and severity of the problem of procrastination |
| B．make an effort to keep the problem of procrastination well under control |
| C．take our time to identify the root problem of the habit of procrastination |
| D．prevent and cope with the issue of procrastination in the early stage |
| A．If we put off the hardest task to the end of the day, we can be more energetic. |
| B．It is of greater importance for us to see the “forest” than attend to the “tree”. |
| C．A small and steady step on the daily basis will make the task less overwhelming. |
| D．Having a second cup of coffee will help you compete morning commitment better. |
| A．trick you into being more anxious and desperate |
| B．keep you more concentrated and productive |
| C．help you move past the initial paralysis you feel |
| D．prevent you from feeling guilty when going to bed at night |
| A．it is quite impossible to completely get rid of procrastination circle |
| B．creating a good plan can help you win the battle against procrastination |
| C．everybody may tend to procrastinate and there is little need for guilt |
| D．with the advice listed, it is very hopeful to overcome procrastination |
10 . Population and climate
The human population on Earth has grown to the point that it is having an effect on Earth’s atmosphere and ecosystems. Burning of fossil fuels, deforestation, urbanization, and cultivation of rice and cattle are increasing the concentration of carbon dioxide, nitrogen oxides and dust in the atmosphere. About 70 percent of the Sun’s energy passes through the atmosphere and strikes Earth’s surface. This radiation heats the surface of the land and ocean, and these surfaces then reradiate infrared radiation back into space. This allows Earth to avoid heating up too much. However, not all of the infrared radiation makes it into space; some is absorbed by gases in the atmosphere and is reradiated back to Earth’s surface. A greenhouse gas is one that absorbs infrared radiation and then reradiates some of this radiation back to Earth. Carbon dioxide and nitrogen oxides are greenhouse gases. In fact, without greenhouse gases in the atmosphere, scientists calculate that Earth would be about 33℃ cooler than it currently is.
The current concentration of carbon dioxide in the atmosphere is about 360 parts per million. Human activities are having a major influence on atmospheric carbon dioxide concentrations, which are rising so fast that current predictions made by scientists are that atmospheric concentrations of carbon dioxide will double in the next 50 to 100 years.
Some scientists predict that a doubling of carbon dioxide concentration will raise global temperatures anywhere between 1.4℃ and 4.5℃. The increase in temperature will not be uniform, with the smallest changes at the equator and changes two or three times as great at the poles. The local effects of these global changes are difficult to predict, but it is generally agreed that they may include alterations in ocean currents, increased winter flooding in some areas of the Northern Hemisphere, a higher incidence of summer drought in some areas, and rising sea levels, which may flood low-lying countries.
1. It can be inferred from the passage that one positive aspect of greenhouse gases is that they _______.| A．remove pollutants from Earth’s atmosphere and ecosystems |
| B．absorb 70 percent of the Sun’s energy |
| C．help keep Earth warm |
| D．double atmospheric concentrations of carbon dioxide |
| A．The rapid rise of atmospheric carbon dioxide concentrations is mostly caused by human activities. |
| B．Human activities will no longer have an influence on atmospheric carbon dioxide concentrations in the next 50 to 100 years. |
| C．Some scientists predict that atmospheric carbon dioxide concentrations will not increase in the next 50 to 100 years. |
| D．Some scientists recently predict that atmospheric carbon dioxide concentrations that are largely influenced by human activities will double in the next 50 to 100 years. |
| A．different |
| B．identical |
| C．comparable |
| D．changeable |
| A．Sea levels will fall. |
| B．The effects will not occur in some regions of the world. |
| C．The local plants and forests will be permanently damaged. |
| D．It is hard to know exactly what form the local effects will take. |
| A．Raising livestock and growing rice are the actions of humans. |
| B．The surface of the land and ocean can help decrease the temperature of Earth. |
| C．Although carbon dioxide concentration may double in the future, temperatures at the North Pole and South Pole may not change. |
| D．Nitrogen oxides absorb infrared radiation that can increase the temperature of Earth. |
