1 . Why isn’t science better? Look at career incentives.
There are often substantial gaps between the idealized and actual versions of those people whose work involves providing a social good. Government officials are supposed to work for their constituents. Journalists are supposed to provide unbiased reporting and penetrating analysis. And scientists are supposed to relentlessly probe the fabric of reality with the most rigorous and skeptical of methods.
All too often, however, what should be just isn’t so. In a number of scientific fields, published findings turn out not to replicate (复制), or to have smaller effects than, what was initially claimed. Plenty of science does replicate — meaning the experiments turn out the same way when you repeat them — but the amount that doesn’t is too much for comfort.
But there are also ways in which scientists increase their chances of getting it wrong. Running studies with small samples, mining data for correlations and forming hypotheses to fit an experiment’s results after the fact are just some of the ways to increase the number of false discoveries.
It’s not like we don’t know how to do better. Scientists who study scientific methods have known about feasible remedies for decades. Unfortunately, their advice often falls on deaf ears. Why? Why aren’t scientific methods better than they are? In a word: incentives. But perhaps not in the way you think.
In the 1970s, psychologists and economists began to point out the danger in relying on quantitative measures for social decision-making. For example, when public schools are evaluated by students’ performance on standardized tests, teachers respond by teaching “to the test”. In turn, the test serves largely as of how well the school can prepare students for the test.
We can see this principle—often summarized as “when a measure becomes a target, it ceases to be a good measure”—playing out in the realm of research. Science is a competitive enterprise. There are far more credentialed (授以证书的) scholars and researchers than there are university professorships or comparably prestigious research positions. Once someone acquires a research position, there is additional competition for tenure (终身教授) grant funding, and support and placement for graduate students. Due to this competition for resources, scientists must be evaluated and compared. How do you tell if someone is a good scientist?
An oft-used metric (标准，度量) is the number of publications one has in peer-reviewed journals, as well as the status of those journals. Metrics like these make it straightforward to compare researchers whose work may otherwise be quite different. Unfortunately, this also makes these numbers susceptible to exploitation.
If scientists are motivated to publish often and in high-impact journals, we might expect them to actively try to game the system (钻空子). And certainly, some do—as seen in recent high-profile cases of scientific fraud (欺诈). If malicious (恶意的) fraud is the prime concern, then perhaps the solution is simply heightened alertness.
However, most scientists are, I believe, genuinely interested in learning about the world, and honest. The problem with incentives is that they can shape cultural norms without any intention on the part of individuals.
1. Which of the following is TRUE according to the passage?| A．Scientists are expected to persistently devoted to exploration of reality. |
| B．The research findings fail to achieve the expected effect. |
| C．Hypotheses are modified to highlight the experiments’ results. |
| D．The amount of science that does replicate is comforting. |
| A．The public. | B．The incentive initiators. |
| C．The peer researchers. | D．The high-impact journal editors. |
| A．Good scientists excel in seeking resources and securing research positions. |
| B．Competition for resources pushes researchers to publish in a more productive way. |
| C．All the credentialed scholars and researchers will take up university professorships. |
| D．The number of publication reveals how scientists are bitterly exploited. |
| A．High-impact journals are encouraged to reform the incentives for publication. |
| B．The peer-review process is supposed to scale up inspection of scientific fraud. |
| C．Researchers are motivated to get actively involved in gaming the current system. |
| D．Career incentives for scientists are expected to consider their personal intention. |
2 . The Old Man and The Sea
The old man took one look at the great fish as he watched the shark close in.
The shark closed fast on the boat and when he hit the fish the old man saw his mouth open and his strange eyes and his sharp teeth as he drove forward in the meat just above the tail. The old man could hear the noise of skin and flesh ripping on the big fish when he threw the fishing spear(叉)into the shark’s head at a place where the line between his eyes crossed with the line that ran straight back from his nose. There were no such lines.
The shark turned over and the old man saw his eye was not alive and then he turned over once again, wrapping himself in the rope.
| A．Finally, he wanted to give up because of lack of strength. |
| B．It was hard for me to escape from the shark but I will try. |
| C．But that was the location of the brain and the old man hit it. |
| D．The old man knew that he was dead but the shark would not accept it. |
| E．I cannot keep him from hitting me, he thought, but maybe I can get him. |
| F．The shark lay quietly for a little while on the surface and the old man watched him. |
3 . The Hardest Novel I’ve Ever Read
For the last three months, I have glared at its fat heavy form on my floor with a vague sense of personal failure. I have opened Ulysses twice, determined to finish it, and managed to get all the way to page 46. I have read so little both times that I have never bothered using a bookmark.
Why do I get stuck?
There are a few other “worthy” works of literature I have yet to read, including Infinite Jest and War and Peace.
The English writer Virginia Woolf thought Ulysses was nonsense as she complained in her diaries about the pressure to finish reading it. By contrast, Vladimir Nabokov, the author who wrote Lolita expressed deep love for it.
Some people love Ulysses, so where am I getting wrong? My ultimate hope is that the struggle will be worth the effort and I can proceed victorious onto page 800 or so, on my third fourth, eighteenth try. Something tells me I will get there in the end.
| A．I’m not entirely sure myself |
| B．A lot of them are weighty tomes (巨著), but I like big books |
| C．It seems that reading Ulysses is a big different experience for everyone. |
| D．Even when staring at pages without absorbing a word, I thought nice thoughts about it |
| E．They, however, only cause me a slight sense of shame that I have not read or enjoyed them |
| F．I have been amused and charmed by the first two or three chapters, and then puzzled and bored. |
4 . “You’d be an intermediate (中级学生),” the clever salesgirl at the Apple Store said brightly. She was talking about the free classes one could sign up for. An intermediate, I thought with pride. “I’ve used Macs since they had green text and discs,” I said, eager to strengthen my position. “And I had a Mac Classic for years.” She smiled, or maybe she was thinking, “If it’s been that long, why are you still an intermediate?”
Why does one remain an intermediate? Sometimes it’s a matter of opportunity: Leaving New England was a blow to my cross-country skiing. No longer living on the banks of a river held up kayaking. Horseback riding, too, requires an opportunity. I know, however, a friend I rode with as a child bought herself a retired police horse in her 40s. A devoted kayaker would not have been prevented by the highways lying between her and rivers.
Sometimes, it’s ability. I have taken up piano later in life. I love music, but I can see that I have no particular gift for it. Gardening was another late job. I wasn’t a natural at that, either.
I admit I’m a little ashamed of being an intermediate. It seems to imply a lack of focus, an unwillingness to push myself to go deeper or further. Do I lack the persistence to become an expert? Am I too easily distracted to put in the 10,000 hours reportedly required to achieve mastery?
Maybe I have to accept that, for now at least, intermediate is my sweet spot. I’ve moved past the frustrations of beginnerhood without meeting the demands of expertise. A beginner is a beginner and an expert is just that. But an intermediate can be low, medium, or high. And wherever you are as an intermediate, you can always go forward, try harder, and learn more.
Who of us can claim to be an expert parent, wife, husband, child, or friend? At best, we’re the high intermediate with much to learn.
1. What did the writer want to prove to the salesgirl in the first paragraph?| A．Her position as a lifelong intermediate. |
| B．Her good knowledge about Apple computers. |
| C．Her eagerness to attend free courses. |
| D．Her ability to afford to buy expensive computers. |
| A．They are only excuses. |
| B．They appear just by accident. |
| C．They are waiting in our life. |
| D．They just come and go. |
| A．The writer’s worries. |
| B．The writer’s disappointments. |
| C．The writer’s curiosities. |
| D．The writer’s doubts. |
| A．It means the possibility to make improvement. |
| B．It marks the beginning to achieve mastery. |
| C．It presents the opportunity to become an expert. |
| D．It rids people of the difficulty to move on. |
5 . Gone are the days when a mother’s place was in the home: in Britain women with children are now as likely to be in paid work as their unburdened sisters. Many put their little darlings in day care long before they start school. Mindful that a poor start can spoil a person’s chances of success later in life, the state has intervened ever more closely in how babies and toddlers are looked after. Inspectors call not only at nurseries but also at homes where youngsters are minded; three-year-olds follow the national curriculum. Child care has increasingly become a profession.
For years after the government first began in 2001 to twist the arms of anyone who looked after an unrelated child to register with the schools, the numbers so doing fell. Kind but clueless neighbours stopped looking after little ones, who were instead herded into formal nurseries or handed over to one of the ever-fewer registered child-minders. The decline in the number of people taking in children now appears to have halted. According to data released by the Office for Standards in Education on October 27th, the number of registered child-minders reached its lowest point in September 2010 and has since recovered slightly.
The new lot are certainly better qualified. In 2010 fully 82% of nursery workers held diplomas notionally equivalent to A-levels, the university-entrance exams taken mostly by 18-year-olds, up from 56% seven years earlier, says Anand Shukla of the Daycare Trust, a charity. Nurseries staffed by university graduates tend to be rated highest by inspectors, increasing their appeal to the pickiest parents. As a result, more graduates are being recruited.
But professionalization has also pushed up the price of child care, defying even the economic depression. A survey by the Daycare Trust finds that a full-time nursery place in England for a child aged under two, who must be intensively supervised, costs £194 ($310) per week, on average. Prices in London and the south-east are far higher. Parents in Britain spend more on child care than anywhere else in the world, according to the OECD, a think-tank. Some 68% of a typical second earner's net income is spent on freeing her to work, compared with an OECD average of 52%.
The price of child care is not only eye-watering, but has also become a barrier to work. Soon after it took power the coalition government pledged to ensure that people are better off in work than on benefits, but a recent survey by Save the Children, a charity, found that the high cost of day care prevented a quarter of low-paid workers from returning to their jobs once they had started a family. The government pays for free part-time nursery places for three-and four-year-olds, and contributes towards day-care costs for younger children from poor areas. Alas, extending such an aid during stressful economic times would appear to be anything but child’s play.
1. Which of the following is true according to the first paragraph?| A．Nursery education plays a leading role in one’s personal growth. |
| B．Pregnant women have to work to lighten families’ economic burden. |
| C．Children in nursery have to take uniform nation courses. |
| D．The supervision of the state makes child care professional. |
| A．the registered child-minders are required to take the university-entrance exams |
| B．the number of registered child-minders has been declining since 2001 |
| C．anyone who looks after children at home must register with the schools |
| D．the growing recognition encourages more graduates to work as child-minders |
| A．prevents mothers from getting employed |
| B．may further depress the national economy |
| C．makes many families live on benefits |
| D．is far more than parents can afford |
| A．Objective. | B．Skeptical. | C．Supportive. | D．Biased. |
| A．The professionalization of child care has pushed up its price. |
| B．The high cost of child nursing makes many mothers give up their jobs. |
| C．The employment of more graduates makes nurseries more popular. |
| D．Parents in Britain pay most for child nursing throughout the world. |
6 . “NON-FUNGIBLE TOKENS” (NFTs) leapt from the more obscure corners of the internet into the mainstream in March 2021 when Christies, a British auction house, sold a digital work of art for $69m. What it actually flogged was an NFT, a cryptocurrency chit that proves a buyer owns an intangible marker connected to a unique piece of digital art, music or other item. Much like René Magritte’s painting of a pipe that proclaims “this is not a pipe” an NFT is not the thing it represents. Tweets, videos of basketball dunks and even the source code to the world wide web have been sold as NFTs in recent months. From June to September they generated almost $11bn in sales, an eight-fold increase on the previous four months, according to DappRadar, a market tracker. What exactly is an NFT? And why are people spending tens of millions of dollars on them?
An NFT is a record on a cryptocurrency’s blockchain (an immutable ledger（不可篡改的账本） that can record more than just virtual coins) that represents pieces of digital media. Invented a few years ago, it can link not only to art but also to text, videos or bits of code. Promoters of NFTs claim that they solve a thorny（棘手的） problem with digital art: how to own an original. For creators who freely upload their work or sell it as identical copies, the concept of an original is difficult to pin down（确定）. Exclusivity is impossible to enforce when digital files can be shared freely on the internet. But collectors want the cachet that comes with having an exclusive claim on an artwork. This is where NFTs fit in.
To mint（铸币，造币） an NFT, the creator establishes a unique record of the artwork, generally on a website. Then the creator places the record on a blockchain, usually Ethereum’s, which requires a transaction fee known as gas. Possession of a private encryption key associated with the transaction proves ownership. This gives an artist or collector something to sell. An NFT may link to a version of the work, but rarely includes the rights to reproduce or distribute it. That differentiates it from a commercial licensing arrangement, too.
NFTs have myriad（众多的） problems. They often change hands using cryptocurrencies, many of which currently have sky-high valuations, leading to fears of a bubble. Anyone can mint an NFT, since the systems involved are decentralised（去中心化的）, although doing so with someone else’s work could be infringe their copyright. Some artists have already claimed misappropriation of their work.Most NFTs are simply links to images. Unless they have been issued in a certain way to ensure they are tamper-proof（防更改的） these can in theory be meddled with after the sale. The high electricity usage of blockchains—Bitcoin’s is greater than that of Chile—has prompted arguments over whether artists are contributing to climate change by embracing NFTs. And ownership may be difficult to prove in the long term, as web-based records may not last for ever.
Yet NFTs have some value beyond the cryptocurrency hype （加密货币炒作）: artists struggle to make a living when their works can be easily replicated and pirated. NFTs will create new problems in an attempt to solve old ones, but for now many creators and collectors are too busy cashing in to care.
1. What can we learn from the first paragraph?| A．What is the core concept of NFTs. | B．Where NFTs can fit in. |
| C．How to make NFTs. | D．What’s the disadvantages of NFTs. |
| A．It seldom change hands using cryptocurrencies. |
| B．The systems involved are centralized. |
| C．The high electricity usage of blockchains possibly contribute to climate change by embracing NFTs. |
| D．It is a record on a cryptocurrency’s blockchain. |
| A．Quote. | B．Analogy. | C．Comparison. | D．Personification |
| A．What is an NFT? |
| B．How to make NFTs? |
| C．NFTs have some value beyond the cryptocurrency hype. |
| D．NFTs have myriad problems. |
7 . As far as we know batteries are playing an important role in our life.We couldn’t live without batteries.Why so? Batteries provide power for anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.
“To provide enough power, we need certain methods with high energy density(密度)”，said Jae Kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope(放射性同位素) battery can provide power density that is much higher than chemical batteries.”
Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro / nanoelectromechanreal systems (M/NEMS). Although nuclear batteries can cause concerns, Kwon said they are safe.
“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”
His new idea is not only in the battery’s size, but also in its semiconductor(半导体). Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.
“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,”Kwon said,“By using a liquid semiconductor, we believe we can minimize that problem.”
Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery. In the future, they hope to increase the battery’s power, shrink its size and try with various other materials. Kwon said that battery could be thinner than the thickness of human hair.
1. According to paragraph 1 and 2,we can learn that________.| A．Batteries can only power small sensors . |
| B．The larger batteries are,the more power they can provide. |
| C．Certain methods with high energy density can provide power abundantly . |
| D．Jae Kwon is a professor of electrical and computer engineering at MU. |
| A．He teaches chemistry at MU. |
| B．He developed a chemical battery. |
| C．He is working on a nuclear energy source. |
| D．He made a breakthrough in computer engineering. |
| A．to show chemical batteries are widely applied. |
| B．to introduce nuclear batteries can be safely used. |
| C．to describe a nuclear-powered system. |
| D．to introduce various energy sources. |
| A．get rid of the radioactive waste |
| B．test the power of nuclear batteries. |
| C．decrease the size of nuclear batteries |
| D．decline the damage to lattice structure. |
| A．uses a solid semiconductor |
| B．will soon replace the present ones. |
| C．could be extremely thin. |
| D．has passed the final test. |
| A．science news report | B．book review |
| C．newspaper advertisement | D．science fiction story |
8 . What is volunteer travel?
Volunteer travel involves taking a trip where all or part of the purpose of the trip is to participate in an arranged service opportunity helping others. Typically, the volunteer activity takes place in a foreign country, but some opportunities can involve national or regional projects.
Charitable interests often go far beyond national boundaries. People in developed countries become interested in the struggles of people in less developed countries.
| A．The primary purpose of the trip was very specific. |
| B．This type of travel has been an option for many years. |
| C．Educational institutions also made volunteer travel an option. |
| D．Sometimes, donating money is not enough to satisfy the need to help. |
| E．The Internet has helped make community service in general more popular. |
| F．These trips are usually arranged by church organizations, human interest groups or non-profits. |
| G．A new trend is that for-profit tour operators arrange group travel around volunteer opportunities. |
9 . Revealing the source of Jupiter’s x-ray auroral flares
Abstract
Jupiter’s rapidly rotating, strong magnetic field provides a natural laboratory that is key to understanding the dynamics (动力学) of high-energy plasmas (等离子体). Spectacular auroral (极光的) X-ray flares (耀斑) are diagnostic of the most energetic processes governing magnetospheres but seemingly unique to Jupiter. Since their discovery 40 years ago, the processes that produce Jupiter’s X-ray flares have remained unknown. Here, we report simultaneous (同时的) in situ satellite and space-based telescope observations that reveal the processes that produce Jupiter’s X-ray flares, showing surprising similarities to terrestrial ion aurora. Planetary-scale electromagnetic waves are observed to modulate (调节) electromagnetic ion cyclotron waves, periodically causing heavy ions to precipitate and produce Jupiter’s X-ray pulses. Our findings show that ion aurorae share common mechanisms across planetary systems, despite temporal, spatial, and energetic scales varying by orders of magnitude.
INTRODUCTION
Aurorae, observed from planetary polar regions across the solar system, are displays of light that are produced when energetic particles precipitate along magnetic field lines and transfer their energy to the atmosphere. Jupiter’s soft x-ray aurorae are produced by energetic [~ (MeV) (电子伏)] heavy ions (S and O), originally from the moon Io’s (木卫一的) volcanic activities. The dynamic X-ray emissions often pulse with a regular beat of a few tens of minutes. The spectacular quasi-periodic (准周期性的) auroral pulsations at Jupiter have also been observed in ultraviolet (UV), infrared, and radio emissions. The X-ray aurorae are predominately confined (主要局限于) to the region poleward of Jupiter’s main aurora, connecting to Jupiter’s outer magnetosphere via magnetic field lines. The mapping of the emissions leads to the suggestion that the particle precipitations were driven by magnetic reconnection. However, observations show that the x-ray pulsations last for several Jupiter days or longer, evidencing that the driver may not be a transient process like magnetic reconnection.
To date, 40 years after their discovery, the mechanisms that cause these X-ray aurorae remain unknown. Simultaneous measurements of the magnetospheric environment and the auroral emissions are critical to revealing their driving mechanisms. Here, we present observations of Jupiter’s unique x-ray aurorae with simultaneous in situ measurements from the magnetosphere. In this study, we reveal the physical driver for Jupiter’s pulsating x-ray emissions by analyzing simultaneous in situ measurements from Juno and remote spectroscopic imaging by XMM-Newton telescope (XMM，牛顿卫星) during 16 and 17 July 2017. XMM’s European Photon Imaging Camera (EPIC-pn and MOS) instruments provided spatial, spectral, and timing data of Jupiter for a continuous 26-hour (~2.6 Jupiter rotations) observation from 18:26 UT on 16 July to 22:13 UT on 17 July, which was shifted to account for the ~46-min light travel time between Jupiter and Earth. This XMM observation was planned to coincide with the time when NASA’s Juno spacecraft was moving from 62 to 68 RJ (1 RJ = 71 492 km) radially away from the planet in the Southern Hemisphere in the predawn sector between ~0400 and 0430 magnetospheric local time (MLT).
Ionosphere-magnetosphere (电离层) mapping from previous observations suggested that the origins of Jupiter’s X-ray auroral pulsations occurred at these distances from the planet. Juno provided contemporaneous (同时发生的) in situ measurements from the plasma sheet only when Jupiter’s north magnetic pole tilted to Earth. Therefore, we focus on the northern aurora, for which Juno’s in situ measurements detail what was happening in the plasma sheet during the X-ray pulses. At Jupiter, the analysis of these comparisons between in situ and remote sensing observations is more complex than at Earth. At Earth, during the time scale of an auroral event, typically tens of minutes, a spacecraft in the terrestrial magnetosphere usually travels little (e.g., hundreds of kilometers) in comparison to the spatial scale of a magnetospheric event (e.g., several Earth radii) that would cause a large auroral brightening so that this in situ spacecraft could be magnetically connected to the aurora region over the full auroral lifetime. This is not true for Jupiter, because the footprint of the aurora (which is rotating with Jupiter) with respect to Juno’s location changes substantially during an observation. There are also substantial travel times (a few tens of minutes) along the magnetic field expected from the outer magnetosphere to the Jovian aurora. Therefore, the correlation between a single outer magnetosphere event in Jupiter’s in situ measurements and a single auroral pulse cannot be expected on a one-to-one level basis. Instead, a series of successive events are required to draw reliable careful correlations, with the regular periodicity of the x-ray flares, providing an invaluable diagnostic signature of the source process.
(Adapted from an essay on Science.)
1. What does the essay focus on?| A．The X-ray pulses happening on Jupiter. |
| B．The formation of the aurora in the pole of Jupiter. |
| C．The ways to teach people how to appreciate auroras. |
| D．The process of detecting the X-ray pulses on Jupiter. |
| A．Their conclusions. | B．Their measure to do the research. |
| C．Discussion of some problems of preciseness. | D．Their acknowledgements. |
| A．辐射 | B．红外线技术的 | C．太阳风 | D．红外线 |
| A．The strong magnetic is a good breakthrough point to research the auroral flares. |
| B．The X-ray pulses will last for several days on Jupiter. |
| C．The soft X-rays are caused by high-energy ions. |
| D．The X-ray pulses beat regular on Jupiter. |
10 . Language Acquisition(习得)
Almost all humans acquire at least one language before the age of five. How do young children understand and produce complex sentences with complicated meanings? Do adults learn language differently from children? Most linguistic(语言学的) researchers agree that both nature and nurture(后天) are involved in language acquisition. They disagree， however， about how much linguistic knowledge children have from birth-and thus whether genetics or experience is more important in language acquisition.
For many linguists， biological factors are the most important in language learning. Some argue that some linguistic knowledge must exist in our brains from birth because children cannot possibly experience every feature of their language before the age of five. These linguists point out that nearly all children can produce the same kinds of complex sentence structures by the age of five， even without having heard them before.
Many researchers have theorized what this innate(先天的) linguistic knowledge must look like. One popular theory(理论) is universal grammar. This theory believes that all languages have the same basic structural foundation. That foundation is the innate knowledge universal to all humans. While children are not genetically tending to speak a particular language， a universal grammar gives them certain linguistic information as a starting point， which allows them to readily acquire the rules and patterns of whichever language they are exposed to.
Not all linguists， however， believe that an inborn ability for language is the most important factor in language acquisition. These researchers place greater emphasis on the influence of usage and experience. They argue that children are exposed to a wealth of linguistic structures over the course of five years. They gather data and determine language patterns and structures from what they have observed.
Linguists on both sides of the debate are still working to explain the different language learning abilities of adults and children. Early childhood seems to be an important period for mastering certain aspects of language. Children also tend to have a heightened ability to learn second languages. While adults may have some advantages when studying in a formal classroom， they usually do not learn second languages. While adults may have some advantages when studying in a formal classroom, they usually do not learn as quickly and easily as children. Are these different abilities a result of differences in how adults and children are exposed to a new language? Are they the result of biological changes， or do both biology and experience come into play?
While our understanding of language acquisition is incomplete, this pursuit is well worth the effort. “We still don’t understand how a child learns its first language, why some children have language disorders, or how children and adults learn a second language,” explains Professor Joan Ma ling.
Explaining the process of language acquisition promises not only to help scientists answer these questions, but also to explain fundamental features of learning and the human brain.
1. What does the passage mainly talk about?| A．The control of nurture over nature in language acquisition. |
| B．The influence of universal grammar in language acquisition. |
| C．The best methods for children and adults to acquire language. |
| D．The role of biological and environmental factors in language acquisition. |
a. Studying language acquisition will help understand language and the brain better.
b. Some experts focus on the role of environmental factors in language acquisition.
c. Some experts believe innate factors explain children's language development.
d. Acquiring a language is complicated， and it involves both nature and nurture.
| A．abcd | B．dcba | C．dbca | D．adcb |
| A．present a general argument and then explain a specific theory |
| B．present a specific theory and then propose a new study to prove it |
| C．present a general argument and then disprove an opposite argument |
| D．present a scientific debate and then discuss what all linguists agree on |
| A．To raise open questions that all linguists have. |
| B．To present two different viewpoints on language learning. |
| C．To stress the importance of experience in language learning |
| D．To introduce adult language acquisition and show why it's unpopular. |
