1 . Fresh fish should have a mild smell. Strong fishy smells are the first signs to go bad. How do the fishy smells come from?
It can be several days from when the fish are caught to when they reach the supermarket. In that time, bacteria that grow naturally in fish start to consume a substance called trimethylamine N-oxide(TMAO)in fish. These bacteria change TMAO into trimethylamine (TMA), the substance responsible for the fishy smells. Bacteria in fish can also change lysine(赖氨酸)into cadaverine(尸胺), a substance that’s associated with breaking down the fish once they are caught and giving off fishy smell.
Chemical reactions can also lead to fishy smells. This happens through the oxidation(氧化)of fat. Fish are an important source of omega-3 fatty acids. When these fats are exposed to oxygen, they oxidize and break down into the substance that you can smell.
To slow down the fishy smell, what is beyond question is that the less time between when the fish are caught and when they reach the kitchen, the better. But today, fish are often flown across the globe. To keep smell-producing bacteria at bay, the fish must be frozen or kept at the low temperature possible as soon as they are caught and cleaned.
Controlling fat oxidation can function as well, especially for fattier fish species. While freezing slows bacterial growth, it does not stop fat oxidation. This reaction will occur as long as oxygen is present. Fatty fish are usually not frozen because, despite the cold temperature, they’re going to oxidize pretty fast unless they are stored in a low oxygen container. That’s why those species are often canned.
It’s also important to remember that smell is not always an indicator of safety, especially in processed fish products. “What you might consider the fishy smell may be a delicacy in another culture,” said Carl A. Batt, a professor of food science at Cornell University.
1. Which of the following has the fishy smell?A.Fish fat. | B.TMAO. | C.Cadaverine. | D.Lysine. |
A.Drying them in the air. | B.Storing them in closed containers. |
C.Carefully cleaning them. | D.Exposing them to rich oxygen. |
A.Objective. |
B.Negative. |
C.Acceptable. |
D.Unclear. |
A.Topic—Example—Conclusion. | B.Topic—Comparison—Opinion. |
C.Question——Cause——Solution. | D.Question—Effect—Opinion. |
2 . On March 7, 1907, the English statistician Francis Galton published a paper which illustrated what has come to be known as the “wisdom of crowds” effect. The experiment of estimation he conducted showed that in some cases, the average of a large number of independent estimates could be quite accurate.
This effect capitalizes on the fact that when people make errors, those errors aren’t always the same. Some people will tend to overestimate, and some to underestimate. When enough of these errors are averaged together, they cancel each other out, resulting in a more accurate estimate. If people are similar and tend to make the same errors, then their errors won’t cancel each other out. In more technical terms, the wisdom of crowds requires that people’s estimates be independent. If for whatever reasons, people’s errors become correlated or dependent, the accuracy of the estimate will go down.
But a new study led by Joaquin Navajas offered an interesting twist (转折) on this classic phenomenon. The key finding of the study was that when crowds were further divided into smaller groups that were allowed to have a discussion, the averages from these groups were more accurate than those from an equal number of independent individuals. For instance, the average obtained from the estimates of four discussion groups of five was significantly more accurate than the average obtained from 20 independent individuals.
In a follow-up study with 100 university students, the researchers tried to get a better sense of what the group members actually did in their discussion. Did they tend to go with those most confident about their estimates? Did they follow those least willing to change their minds? This happened some of the time, but it wasn’t the dominant response. Most frequently, the groups reported that they “shared arguments and reasoned together”. Somehow, these arguments and reasoning resulted in a global reduction in error. Although the studies led by Navajas have limitations and many questions remain, the potential implications for group discussion and decision-making are enormous.
1. What is paragraph 2 of the text mainly about?A.The methods of estimation. | B.The underlying logic of the effect. |
C.The causes of people’s errors. | D.The design of Galton’s experiment. |
A.the crowds were relatively small | B.there were occasional underestimates |
C.individuals did not communicate | D.estimates were not fully independent |
A.The size of the groups. | B.The dominant members. |
C.The discussion process. | D.The individual estimates. |
A.Unclear. | B.Dismissive. | C.Doubtful. | D.Approving. |
3 . Mental Health Crisis Among Teens Demands a New Approach
Since the CDC released its survey results last month showing alarmingly high rates of sadness and depressive thoughts among teens, fingers have been pointed from two sides at the causes of this crisis.
According to the CDC’s findings, more than one in five of the 17,000 high school students surveyed reported mental breakdown. Their rates of sadness and hopelessness are the highest in a decade, reflecting an increasing trend exacerbated by society’s isolation(隔离)and stress.
Parents as well as teachers and others who have direct contact with children must accept this preventive approach. It is crucial that they not be afraid to ask direct questions about depressive thoughts.
A.And they should resist the false idea that raising a question creates a risk that was not there before. |
B.This means that we must put aside our disagreements and approach this issue as a matter of life and death. |
C.Some have argued that the climate issue has created an existential threat and accompanying anxiety. |
D.Hospitalization may also be appropriate when the person in question shows an immediate danger to themselves. |
E.At the macro(宏观的)level, our country can do so much more to help people struggling with mental health problems and their families. |
F.It’s time to stop blaming and turn our attention to this generation of struggling teenagers. |
G.It’s time for those who have the power to amplify(放大)their voices and drive change to focus on helping teenagers and families access the help they need. |
4 . “Two centuries ago, Lewis and Clark left St. Louis to explore the new lands acquired in the Louisiana Purchase,” George W. Bush said, announcing his desire for a program to send men and women to Mars. They made that journey in the spirit of discovery. America has ventured forth into space for the same reasons.
Yet there are vital differences between Lewis and Clark’s expedition and a Mars mission. First, they were headed to a place where hundreds of thousands of people were already living. Second, they were certain to discover places and things of immediate value to the new nation. Third, their venture cost next to nothing by today’s standards. A Mars mission may be the single most expensive non-wartime undertaking in U.S. history.
Appealing as the thought of travel to Mars is, it does not mean the journey makes sense, even considering the human calling to explore. And Mars as a destination for people makes absolutely no sense with current technology.
Present systems for getting from Earth’s surface to low-Earth orbit are so fantastically expensive that merely launching the 1,000 tons or so of spacecraft and equipment a Mars mission would require could be accomplished only by cutting health-care benefits, education spending, or other important programs—or by raising taxes. Absent (缺乏)some remarkable discovery, astronauts, geologists, and biologists once on Mars could do little more than analyze rocks and feel awestruck (敬畏的) staring into the sky of another world. Yet rocks can be analyzed by automated probes without risk to human life, and at a tiny portion of the cost of sending people.
It is interesting to note that when President Bush unveiled (公开) his proposal, he listed these recent major achievements of space exploration: pictures of evidence of water on Mars, discovery of more than 100 planets outside our solar system, and study of the soil of Mars. All these accomplishments came from automated probes or automated space telescopes. Bush’s proposal, which calls for reprogramming some of NASA’s present budget into the Mars effort, might actually lead to a reduction in such unmanned science—the one aspect of space exploration that’s working really well.
Rather than spend hundreds of billions of dollars to hurl (投) tons toward Mars using current technology, why not take a decade or two or however much time is required researching new launch systems and advanced propulsion (推进力)? If new launch systems could put weight into orbit affordably, and advanced propulsion could speed up that long, slow transit (运输) to Mars, the dream of stepping onto the red planet might become reality. Mars will still be there when the technology is ready.
1. What do Lewis and Clark’s expedition and a Mars mission have in common?A.Instant value. | B.Human inhabitance. |
C.Venture cost. | D.Exploring spirit. |
A.great achievements have already been made in Mars exploration in America. |
B.American people’s well-being will suffer a lot if it is carried out. |
C.its expense is too huge for the government to afford. |
D.unmanned Mars exploration sounds more practical and economical for the moment. |
A.Going to Mars using current technology is quite sensible. |
B.A Mars mission will in turn promote the development of unmanned program. |
C.Bush’s proposal is based on three recent great achievements of space exploration. |
D.The achievements in space exploration show how well manned science has developed. |
A.Risky as it is, a Mars mission helps maintain America’s position as a technological leader. |
B.A Mars mission is so costly that it may lead to an economic disaster in America. |
C.Someday people may go to Mars but not until it makes technological sense. |
D.A Mars mission is unnecessary since the scientists once there won’t make great discoveries. |
5 . The environmental practices of big businesses are shaped by a fundamental fact that offends our sense of justice. A business may maximize the amount of money it makes by damaging the environment and hurting people. When government regulation is effective, and the public is environmentally aware, environmentally clean big businesses may out-compete dirty ones, but the reverse is likely to be true if government regulation is ineffective and the public doesn’t care.
It is easy to blame a business for helping itself by hurting other people. But blaming alone is unlikely to produce change. It ignores the fact that businesses are not charities but profit-making companies, and they are under obligation to maximize profits for shareholders by legal means.
Our blaming of businesses also ignores the ultimate responsibility of the public for creating the conditions that let a business profit through destructive environmental policies. In the long run, it is the public, either directly or through its politicians, that has the power to make such destructive policies unprofitable and illegal, and to make sustainable environmental policies profitable.
The public can do that by accusing businesses of harming them. The public may also make their opinion felt by choosing to buy sustainably harvested products; by preferring their governments to award valuable contracts to businesses with a good environmental track record; and by pressing their governments to pass and enforce laws and regulations requiring good environmental practices.
In turn, big businesses can exert powerful pressure on any suppliers that might ignore public or government pressure. For instance, after the US public became concerned about the spread of a disease, transmitted to humans through infected meat, the US government introduced rules demanding that the meat industry abandon practices associated with the risk of the disease spreading. But the meat packers refused to follow these, claiming that they would be too expensive to obey. However, when a fast-food company made the same demands after customer purchases of its hamburgers dropped, the meat industry followed immediately. The public’s task is therefore to identify which links in the supply chain are sensitive to public pressure.
Some readers may be disappointed or outraged that I place the ultimate responsibility for business practices harming the public on the public itself. I also believe that the public must accept the necessity for higher prices for products to cover the added costs of sound environmental practices. My views may seem to ignore the belief that businesses should act in accordance with moral principles even if this leads to a reduction in their profits. But I think we have to recognize that, throughout human history, government regulation has arisen precisely because it was found that not only did moral principles need to be made explicit, they also needed to be enforced.
My conclusion is not a moralistic one about who is right or wrong, admirable or selfish. I believe that changes in public attitudes are essential for changes in businesses’ environmental practices.
1. The main idea of Paragraph 3 is that environmental damage__________.A.is the result of ignorance of the public |
B.requires political action if it is to be stopped |
C.can be prevented by the action of ordinary people |
D.can only be stopped by educating business leaders |
A.reduce their own individual impact on the environment |
B.learn more about the impact of business on the environment |
C.raise awareness of the effects of specific environmental disasters |
D.influence the environmental policies of businesses and governments |
A.Meat packers stopped supplying hamburgers to fast-food chains. |
B.Meat packers persuaded the government to reduce their expenses. |
C.A fast-food company forced their meat suppliers to follow the law. |
D.A fast-food company encouraged the government to introduce regulations. |
A.Will the world survive the threat caused by big businesses? |
B.How can big businesses be encouraged to be less driven by profit? |
C.What environmental dangers are caused by the greed of businesses? |
D.Are big businesses to blame for the damage they cause to the environment? |
6 . ‘Small Data’ Are Also Crucial for Machine Learning
Many people relate “artificial intelligence” with “big data.” There’s a reason for that: some of the most prominent AI breakthroughs in the past decade have relied on enormous data sets. Image
Also known as “fine-tuning,” transfer learning is helpful in settings where you have
Small data approaches such as transfer learning are more
Despite the progress in research, transfer learning has received relatively little
As long as the success of small data technique like transfer learning is
A.standard | B.classification | C.quality | D.acquisition |
A.written | B.limited | C.spoken | D.abundant |
A.moral | B.visual | C.literary | D.popular |
A.complicated | B.interesting | C.promising | D.distinguished |
A.extra | B.different | C.available | D.few |
A.personal | B.specific | C.technical | D.potential |
A.in addition | B.or rather | C.in particular | D.for example |
A.adjust | B.invent | C.follow | D.check |
A.definite | B.advantageous | C.complex | D.precise |
A.remotely | B.severely | C.ultimately | D.rarely |
A.underexplored | B.underestimated | C.underpopulated | D.underqualified |
A.guidance | B.respect | C.supervision | D.visibility |
A.publication | B.adoption | C.tracking | D.polishing |
A.celebrated | B.evaluated | C.recognized | D.diversified |
A.challenge | B.concern | C.fear | D.misunderstanding |
7 . The “reading wars,” one of the most confusing and disabling conflicts in the history of education, went on heatedly in the 1980s and then peace came. Advocates of phonics (learning by being taught the sound of each letter group) seemed to defeat advocates of whole language (learning by using cues like context and being exposed to much good literature).
Recent events suggest the conflict of complicated concepts is far from over. Teachers, parents and experts appear to agree that phonics is crucial, but what is going on in classrooms is not in agreement with what research studies say is required, which has aroused a national debate over the meaning of the word “phonics.”
Lucy M. Calkins, a professor at Columbia University’s Teachers College and a much-respected expert on how to teach reading, has drawn attention with an eight-page essay. Here is part of her argument: “The important thing is to teach kids that they needn’t freeze when they come to a hard word, nor skip past it. The important thing is to teach them that they have resources to draw upon, and to use those resources to develop endurance.”
To Calkins’s critics, it is cruel and wasteful to encourage 6-year-olds to look for clues if they don’t immediately know the correct sounds. They should work on decoding — knowing the pronunciation of every letter group — until they master it, say the critics, backed by much research.
Calkins’s approach “is a slow, unreliable way to read words and an inefficient way to develop word recognition skill,” Mark S. Seidenberg, a psychologist at the University of Wisconsin, said in a blog post. “Dr. Calkins treats word recognition as a reasoning problem — like solving a puzzle. She is committed to the educational principle that children learn best by discovering how systems work rather than being told.”
Many others share his view. “Children should learn to decode — i.e., go from print on the page to words in the mind — not by clever guesswork and inference, but by learning to decode,” Daniel Willingham, a psychologist at the University of Virginia, told me. He said the inferences Calkins applauds are “cognitively (认知地) demanding, and readers don’t have much endurance for it. … It disturbs the flow of what you’re reading, and doing a lot of it gets frustrating.”
Yet a recent survey found that only 22 percent of 670 early-reading teachers are using the approach of phonics and what they mean by phonics is often no more than marking up a worksheet.
Both sides agree that children need to acquire the vocabulary and background information that gives meaning to words. But first, they have to pronounce them correctly to connect the words they have learned to speak.
Calkins said in her essay: “Much of what the phonics people are saying is praiseworthy,” but it would be a mistake to teach phonics “at the expense of reading and writing.”
The two sides appear to agree with her on that.
1. Critics of phonics hold the opinion that ________.A.children should be taught to use context |
B.teaching phonics is both boring and useless |
C.kids acquire vocabulary in hearing letter groups |
D.pronunciation has nothing to do with meaning of words |
A.Tell me and I will forget; show me and I will remember. |
B.Skilled reading is fast and automatic but not deliberative. |
C.Word recognition skill should be developed in problem reasoning. |
D.Learning to make reasonable inferences is also a way of decoding. |
A.phonics approach has been proved to be successful |
B.children don’t shy away from difficulties in reading |
C.the two reading approaches might integrate with each other |
D.reading and writing are much more important than phonics |
A.An everlasting reading war among critics |
B.From print on the page to words in the mind |
C.A battle restarts between phonics, whole language |
D.Decoding and inferring confuse early-reading teachers |
8 . We’ve dug deep to find 4 of the most exciting documentary films coming to a screen near you in 2022.
Last Exit: Space
Last Exit: Space, narrated by Werner Herzog, explores the human potential for settling in space and sending people where they’ve never been before. Since planet Earth is possibly going to hell (地狱) in a handbasket, the film promises to ask the question: where else might we call home? Directed by his son Rudolph Herzog, Last Exit: Space will be available from March 10 on Discovery.
Gorbachev. Heaven
As leader of the Soviet Union Mikhail Gorbachev was once one of the most powerful people on the planet who governed a landmass so big that it covered 11 time zones. Gorbachev’s legacy is a complex one — he oversaw the end of the Cold War but many Russians blame him for the Soviet Union’s collapse. The BBC says this potentially fascinating look at one of the most significant figures from inside his own home will be airing in the very near future.
We Met In Virtual Reality
This film from director Joe Hunting beats fresh ground in that it is filmed entirely in virtual reality. Less about the technology itself, it is more an exploration of human connections and how these can develop in the 3D virtual world. Early reviews have been positive following its showing at Sundance. Expect a streaming release in late May this year.
2nd Chance
Hold your popcorn tightly when watching this. If the trailer (预告片) is anything to go by, there are going to be lots of near-death moments. 2nd Chance from Oscar-nominated director Ramin Bahrani tells the story of Richard Davis, the wild and odd inventor of the modern bullet-proof vest. “All will be revealed as soon as a release date is confirmed.” Ramin Bahrani promised on April 5th.
1. What is probably the major concern in Last Exit: Space?A.Space travel is difficult for people. |
B.Human beings may go to hell after death. |
C.Human beings can’t find their way back from space. |
D.The earth will become unfit for human habitation. |
A.Last Exit: Space. | B.Gorbachev. Heaven. |
C.We Met In Virtual Reality. | D.2nd Chance. |
A.Science & Technology. | B.Fashion & Beauty. |
C.Culture & Entertainment. | D.Travel & Adventure. |
9 . Both misinformation, which includes honest mistakes, and disinformation, which involves an intention to mislead, have had a growing impact on teenage students over the past 20 years. One tool that schools can use to deal with this problem is called media literacy education. The idea is to teach teenage students how to evaluate and think critically about the messages they receive. Yet there is profound disagreement about what to teach.
Some approaches teach students to distinguish the quality of the information in part by learning how responsible journalism works. Yet some scholars argue that these methods overstate journalism and do little to cultivate critical thinking skills. Other approaches teach students methods for evaluating the credibility of news and information sources, in part by determining the incentive of those sources. They teach students to ask: What encouraged them to create it and why? But even if these approaches teach students specific skills well, some experts argue that determining credibility of the news is just the first step. Once students figure out if it’s true or false, what is the other assessment and the other analysis they need to do?
Worse still, some approaches to media literacy education not only don’t work but might actually backfire by increasing students’ skepticism about the way the media work. Students may begin to read all kinds of immoral motives into everything. It is good to educate students to challenge their assumptions, but it’s very easy for students to go from healthy critical thinking to unhealthy skepticism and the idea that everyone is lying all the time.
To avoid these potential problems, broad approaches that help students develop mindsets in which they become comfortable with uncertainty are in need. According to educational psychologist William Perry of Harvard University, students go through various stages of learning. First, children are black-and-white thinkers—they think there are right answers and wrong answers. Then they develop into relativists, realizing that knowledge can be contextual. This stage is the one where people can come to believe there is no truth. With media literacy education, the aim is to get students to the next level—that place where they can start to see and appreciate the fact that the world is messy, and that’s okay. They have these fundamental approaches to gathering knowledge that they can accept, but they still value uncertainty.
Schools still have a long way to go before they get there, though. Many more studies will be needed for researchers to reach a comprehensive understanding of what works and what doesn’t over the long term. “Education scholars need to take an ambitious step forward,” says Howard Schneider, director of the Center for News Literacy at Stony Brook University.
1. As for media literacy education, what is the author’s major concern?A.How to achieve its goal. | B.How to measure its progress. |
C.How to avoid its side effects. | D.How to promote its importance. |
A.Importance. | B.Variety. | C.Motivation. | D.Benefit. |
A.compare different types of thinking |
B.evaluate students’ mind development |
C.explain a theory of educational psychology |
D.stress the need to raise students’ thinking levels |
A.Media Literacy Education: Much Still Remains |
B.Media Literacy Education: Schools Are to Blame |
C.Media Literacy Education: A Way to Identify False Information |
D.Media Literacy Education: A Tool for Testing Critical Thinking |
10 . Albert Einstein’s 1915 masterpiece “The Foundation of the General Theory of Relativity” is the first and still the best introduction to the subject, and I recommend it as such to students. But it probably wouldn’t be publishable in a scientific journal today.
Why not? After all, it would pass with flying colours the tests of correctness and significance. And while popular belief holds that the paper was incomprehensible to its first readers, in fact many papers in theoretical physics are much more difficult.
As the physicist Richard Feynman wrote, “There was a time when the newspapers said that only 12 men understood the theory of relativity. I do believe there might have been a time when only one man did, because he was the only guy who caught on, before he wrote his paper. But after people read the paper a lot understood the theory of relativity in some way or other, certainly more than 12.”
No, the problem is its style. It starts with a leisurely philosophical discussion of space and time and then continues with an exposition of known mathematics. Those two sections, which would be considered extraneous today, take up half the paper. Worse, there are zero citations of previous scientists’ work, nor are there any graphics. Those features might make a paper not even get past the first editors.
A similar process of professionalization has transformed other parts of the scientific landscape. Requests for research time at major observatories or national laboratories are more rigidly structured. And anything involving work with human subjects, or putting instruments in space, involves piles of paperwork.
We see it also in the Regeneron Science Talent Search, the Nobel Prize of high school science competitions. In the early decades of its 78-year history, the winning projects were usually the sort of clever but naive, amateurish efforts one might expect of talented beginners working on their own. Today, polished work coming out of internships(实习) at established laboratories is the norm.
These professionalizing tendencies are a natural consequence of the explosive growth of modern science. Standardization and system make it easier to manage the rapid flow of papers, applications and people. But there are serious downsides. A lot of unproductive effort goes into jumping through bureaucratic hoops(繁文缛节), and outsiders face entry barriers at every turn.
Of course, Einstein would have found his way to meeting modern standards and publishing his results. Its scientific core wouldn’t have changed, but the paper might not be the same taste to read.
1. According to Richard Feynman, Einstein’s 1915 paper ________.A.was a classic in theoretical physics |
B.turned out to be comprehensible |
C.needed further improvement |
D.attracted few professionals |
A.Unrealistic. | B.Irrelevant. |
C.Unattractive. | D.Imprecise. |
A.The application of research findings. |
B.The principle of scientific research. |
C.The selection of young talents. |
D.The evaluation of laboratories. |
A.What makes Einstein great? |
B.Will science be professionalized? |
C.Could Einstein get published today? |
D.How will modern science make advances? |