Electric cars are getting cheaper and their sales are on the rise, but their future success may depend on abandoning a key ingredient: the heavy metal cobalt (钴). The mineral is used in lithium-ion (锂离子) batteries that power most electric cars, and demand for it is steadily increasing. A new analysis by Elsa Olivetti at the Massachusetts Institute of Technology has found that there may be cobalt shortages if we don't start refining (提炼) and recycling it more efficiently or in greater quantities. She estimates that global demand for cobalt will rise to between 235,000 and 430,000 tonnes by 2030 — an amount that is at least 1.6 times the world's current ability to refine the metal, as of 2016 figures.
Cobalt is often produced as a by-product of copper or nickel mining. It is expensive, at around $33,000 per tonne, and also comes with a human cost. Most of the world's supply — 60 per cent— comes from the Democratic Republic of the Congo, where mining has been linked to child labour and deaths.
The new analysis suggests short-term cobalt supply is adequate, but that more mining exploration, such as in the ocean, is required. In addition, we will need to speed up cobalt recycling by recovering it from batteries in unusable electric cars, laptops and mobile phones. Another option is to shift to batteries that use less cobalt, or none at all. Elon Musk's car firm Tesla is in talks with battery manufacturer CATL to use entirely cobalt-free batteries in its China-made cars.
Lithium-ion batteries in electric cars commonly use either lithium nickel cobalt aluminium oxide or lithium nickel manganese cobalt oxide for their ability to provide a high energy density — a key factor in how far an electric car can go on a single charge. For short-range cars made and sold in China, Tesla claims that it will instead use lithium iron phosphate (LiFePO 4 ) (磷酸铁锂) batteries, which are much cheaper and have a longer lifespan (寿命). Besides, they have less of an environmental impact compared with those needing cobalt. The disadvantage is that they tend to have a lower energy density, reducing how far a car can travel without needing to be charged.
LiFePO 4 batteries are already widely used by other Chinese firms, including BYD, the world's biggest electric car manufacturer. If other electric car manufacturers follow internationally, we may be able to reduce our dependence on a limited mineral resource.
1. What is Elsa Olivetti's prediction?| A．Cobalt will be needed badly. |
| B．Cobalt will be recycled efficiently. |
| C．Cobalt will be refined in a different way. |
| D．Cobalt will be replaced by other heavy metals. |
| A．Turning to renewable energy sources. |
| B．Choosing batteries produced by Tesla. |
| C．Decreasing the number of private vehicles. |
| D．Making the best use of abandoned batteries. |
| A．are more expensive | B．are more eco-friendly |
| C．have fewer life cycles | D．offer more usable energy |
| A．Cobalt: a new choice for batteries |
| B．How do lithium-ion batteries work? |
| C．Tesla vs. BYD: a tough competition |
| D．Can electric cars kick the cobalt habit? |
相似题推荐
【推荐1】“If you don't behave, I'll call the police”is a lie that parents might use to get their young children to behave. A new psychological(心理学的) study led by Nanyang Technological University, Singapore suggests that it is connected with harmful effects when the children become adults.
The research team asked 379 Singaporean young adults whether their parents lied to them when they were children, how much they lie to their parents as adults, and how well they respond adulthood challenges.
The first questionnaire asked these young adults to recall if their parents told them lies about eating, leaving or staying, spending money and so on. Some examples of such lies are “If you don't come with me now, I will leave you here by yourself”and“I don’t bring money with me today, we can come back another day”.The second questionnaire included questions that could show how often they lie to their parents as adults. Lastly, these young adults filled in two other questionnaires that asked them about their psychological problems and tendency (趋势)to behave selfishly and impulsively(冲动地).
Adults who reported being lied to more as children were more likely to report lying to their parents in their adulthood. They also said they faced greater difficulty in meeting psychological and social challenges.
Lead author Setoh Peipei from NTU Singapore's School of Social Sciences said, “Parenting by lying can seem to save time, especially when the real reasons behind why parents want children to do something are difficult to explain. When parents tell children that‘honesty is the best policy’，but display dishonesty by lying, such behavior can send negative messages to their children. Parents' dishonesty may finally erode trust and encourage dishonesty in children”
“Our research suggests that parenting by lying is a practice that has negative influence on children when they grow up. Parents should be aware of these possible risks and consider other ways to replace lying, such as knowing children's feelings, giving information so children know what to expect, offering choices and solving problems together, to encourage children to have good behavior, ”said lead author Setoh Peipei.
But the study has its limitations. Some limitations of the study include depending on what young adults report about their parents' lying. “Future research can explore using many informants(提供信息的人), such as parents, to report on the same thing”suggested Setoh.
1. What did the research team do during the study?| A．They turned to 379 Singaporean children |
| B．They looked for questionnaires on the Internet. |
| C．They collected answers to some sets of questions |
| D．They asked the young adults parents for information |
| A．build | B．enhance | C．destroy | D．recover |
| A．Parents can sometimes tell harmless lies to their kids |
| B．Parents had better explain to their kids why they’ve lied |
| C．Parents who like lying are more likely to behave selfishly |
| D．Parents should use positive ways instead of lying during parenting |
| A．Parents 'lying to children can influence them negatively |
| B．Parents lie to children to save themselves some trouble. |
| C．Children's behavior can be affected by their parents |
| D．Children may lie more if their parents often lie. |
【推荐2】What's the Mere Exposure Effect?
Has it ever occurred to you that you started liking that song you used to hate because you had listened to it repeatedly? Have you ever noticed how, the more time you spend with a person, the more pleasant he/she becomes?
Robert Zajonc is one of the authors who studied this particular psychological effect. He proved the presence of this preference in the face of stimuli of a very diverse nature. Words, sounds, photographs of faces…
Researchers conducted a study to test the influence of this effect on the liking for certain foods. For this, they gave a group of students several juices they didn't know until that moment.
Fechner, a German psychologist, the father of some current psychophysical theories, offers an explanation for this effect.
However, you must keep in mind that you can get bored if repeated exposure to the stimulus becomes excessive.
This principle of familiarity is the foundation of many of your preferences, regardless of your greater or lesser taste for adventure and risk. The products you buy, the places you frequent, and the people you like can all be affected by this principle. Therefore, it's convenient to be aware of its influence on your mind.
| A．This is what the mere-exposure effect is about. |
| B．The reason for the mere exposure effect is uncertain. |
| C．Some tried them five times, others 10, and others 15 |
| D．People tend to react with fear or anxiety to new elements. |
| E．If you eat the same thing every day, you'll end up hating it. |
| F．In all cases, people seem to favor those most familiar to them. |
| G．The effect happens due to their fear of new challenges and threats. |
【推荐3】We often see beautiful butterflies flying around us. If you have ever tried to catch a resting butterfly, you know it is surprisingly difficult. A new study helps explain why.
Previous research had suggested that a butterfly’s overhead wing clap forces the insect forward. Researchers thought the wing clap likely formed a pocket of air that shoots out like a jet. But no one had tested that until now.
To analyze their flight, they placed six butterflies one at a time inside a wind cave which was filled with smoke and then used a laser (激光灯) to light up the smoke just behind the butterfly. Four high-speed cameras were placed in the cave to take photos of the movement of the butterfly and the smoke as the butterfly was taking off. This let the researchers create a 3D picture of that air movement as the insect flapped its wings.
They analyzed a total of 25 takeoffs by six butterflies. Each included up to three wing beats after takeoff. The butterflies proved more likely to clap their wings together during the first few wing beats than later in flight.
The photos show that forces created by the wings give rise to a flight path. The butterflies rise as their wings move down and shoot forward as their wings move up. A wing clap on takeoff, paired with a quick turn, allowed the butterflies to fly away quickly. They also noticed the wings formed an air pocket just before clapping and that the wings’ flexibility and this pocket improved the jet force created by the clap.
“The study is exciting,” says Ayodeji Bode-Oke, a mechanical engineer in Charlottesville. That means “we have solved the longtime puzzle about how butterflies fly, and it proves nothing is impossible on the road of scientific research. I can’t wait to learn about how the study might inform designs for small flying vehicles.”
1. Why was laser used in the experiment?| A．To frighten the butterflies into flying. |
| B．To help take clear photos of air movement. |
| C．To help researchers observe the butterflies. |
| D．To guide the butterflies through the smoke. |
| A．Butterflies fly forward as wings move down. |
| B．An air pocket forms after butterflies clap wings. |
| C．Upward wing movements help butterflies fly forward. |
| D．Butterflies beat wings three times before taking off. |
| A．Why Can Butterflies Fly Like a Jet? |
| B．How Can Butterflies Make Wing Claps? |
| C．How Can Butterflies Make Quick Turns? |
| D．Why Can Butterflies Run Away Quickly? |
【推荐1】In the past, many people depended on horses for transportation, farming and other kinds of work. A lot of people still like to ride horses for sport. Horse racing and betting on horse racing are also popular. So, it is not surprising that Americans use a lot of expressions about horses.
Long ago, people who were rich or important rode horses that were very tall. Today, if someone acts better than everyone else, you might tell him to "get off your high horse."
And if someone is pushing you to do something, you can say, "Hold your horses!" This is a very informal way to tell someone to calm down and wait. You would not use it with your boss but you could use it with children.
Something else you could say to children if they are playing too rough or hitting each other is to stop horsing around! When kids horse around, they could get hurt. However, kids who live in a one-horse town might have nothing to do but horse around. A one-horse town is a small town with not too much going on.
So, if you live in a one-horse town, you might like to watch a lot of television. Imagine that you are watching your favorite show when your phone rings. You do not answer it. Wild horses could not drag you away from the television. Nothing could stop you from doing what you want to do.
When you get news directly from the best source, you get it straight from the horse's mouth. If your teacher, for example, tells you there is going to be a test tomorrow, you got that information straight from the horse's mouth.
Sometimes a person keeps arguing a question that has already been settled. They are beating a dead horse. A dead horse is quite different from a dark horse. A dark horse is a person who surprises others by doing better than unexpected. In politics, a dark-horse candidate is someone who is not likely to win ... but then does.
1. What is the passage meant to tell us?| A．Reasons why expressions about horses are used |
| B．Some expressions about horses used by Americans. |
| C．The popularity of horse riding in American society. |
| D．Different situations where horses are made use of. |
| A．Get off you high horse. | B．Stop horsing around. |
| C．Hold your horses. | D．Beat a dead horse . |
| A．dark horse | B．dead horse |
| C．wild horse | D．high horse |
【推荐2】It may not be rocket science, but researchers have found aerospace engineers and neurosurgeons (神经外科医生) are not necessarily brighter than the general population.
Researchers examined data from an international group of 329 aerospace engineers and 72 brain surgeons who completed 12 tasks online using the Great British Intelligence Test.
The tasks examined various aspects of cognition (认知), including planning and reasoning, working memory, attention, and emotion processing abilities. The researchers then compared the results against those previously gathered from more than 18,000 members of the British public.
The findings, which were recently published, reveal that only neurosurgeons showed a significant difference, with quicker problem-solving speed but slower memory recall compared with the general population. “The difference in problem-solving speed exhibited by neurosurgeons might arise from the fast-paced nature of neurosurgery, which attracts those with a pre-existing talent for rapid processing, or it could be, though less likely, a product of training for rapid decision-making in time-critical situations,” the researchers noted.
The researchers said the study was, in part, carried out to lay to rest the question of whether one of the professions had the intellectual upper hand-a tension made famous by a comedy show in which a confident neurosurgeon is slapped down by an aerospace expert who says, “Brain surgery... it’s not exactly rocket science, is it?”
However, the team found few differences between the cognitive abilities of aerospace engineers and neuroscientists, although the results suggest the former had higher scores for attention and mental control—such as turning objects in one’s head—while neurosurgeons showed higher scores in semantic (语义的) problem solving—such as definitions of rare words.
“Essentially what we think it shows is that everyone has a range of skills, some people are better at some things and other people are better at other things, and it is very difficult to be better in everything across the board,” said Aswin Chari, an author of the study.
1. What is paragraph 3 mainly about?| A．The research subjects. | B．The research method. |
| C．The research aspects. | D．The research background. |
| A．Fast development of neurosurgery. | B．Talent of neurosurgeons. |
| C．Training for rapid decision-making. | D．Nature of problem solving. |
| A．attempted to answer the question asked by the aerospace expert in the show |
| B．were eager to solve the conflicts between neurosurgeons and aerospace engineers |
| C．intended to settle the argument over the intellectual superiority of the two professions |
| D．wanted to find out which of the two professions was more intellectually demanding |
| A．To inform people of the results of a cognitive study. |
| B．To encourage people to be confident in themselves. |
| C．To reduce prejudice against certain professions. |
| D．To correct misunderstandings about intelligence. |
Their study of hundreds of men and women also found that people who feel satisfied with their lives always have lots of close friends and regularly make new ones.
While it is not clear whether our friends make us happy or we make friends because we are happy, the researchers say it is clear that we should maintain our friendships. Psychologist Richard Tunney said, “Whatever the reason is, actively working on friendships in the same way as to maintain a marriage is a prerequisite (必备条件) to happiness.”
Dr.Tunney, of Nottingham University, quizzed more than 1,700 people about their satisfaction with their lives and the state of their friendships. Those with five friends or fewer had just a 40 percent chance of being happy.
In other words they were more likely to be unhappy than happy. Ten was the first number at which people were more likely to be happy than unhappy. The happiest people were those with dozens of friends, according to the study, which was carried out for the National Lottery (彩票).
For women, this meant having 33 friends; for men, the number was 49. Dr. Tunney said, “People who were extremely satisfied with their lives had twice the number of friends of people who were extremely dissatisfied.” Women tended to have fewer friends than men but formed tighter relationships.
Interestingly, the study found that childhood friends are no more likely to make us happy than people we become close to later in life. Lottery winners, however, have a different opinion on life.They are always happier than others despite spending their time with a small circle of old friends. This could be because they trust people they’ve known for a long time.
1. What’s the best title for this passage?
| A．The Secret to Happiness Is to Make New Friends |
| B．Having at Least 10 Good Friends Makes People Happy |
| C．Why Most People Like to Make Friends Regularly |
| D．Men’s and Women’s Friends Are Different |
| A．People with few friends are sure to be unhappy. |
| B．Our friends can make us happy. |
| C．Happiness may come from a good marriage life. |
| D．We may become happier if we have more friends. |
| A．enjoy making new friends |
| B．make new friends easily |
| C．like staying with old friends |
| D．have no time to make friends |
| A．it’s enough for one person to have ten friends |
| B．unhappy people must have few friends |
| C．childhood friends make people happier than adulthood ones |
| D．friendships play a major role in people’s life |
【推荐1】Have you ever wondered what you would look like if you were an Asian, Middle Eastern, black, white or Indian person? By stepping into the Human Race Machine, you can find out. When you sit inside it, the machine creates a digital image of your face. After pushing certain buttons, the machine uses various photos of people of a certain ethnic group mixed with your own facial features. From this, it can come up with an image showing how you would look as a member of a different race.
The machine is part of a traveling retrospective(回顾展) called “ Seeing and Believing: The Art of Nancy Burson. ” Burson is a famous American photographer and inventor. The show of 100 photos and multimedia works was on view at the Grey Art Gallery in New York on April 20.
“ It is a strange feeling, just like stepping into someone else’s skin. ” said Hathy Zajchenko, a museum visitor from Pennsylvania, US. As soon as she sat down, she tried out a range of ethnic groups. “The Middle Eastern image worked pretty well for me,” she said with a smile.
According to Burson, the machine is a prayer for unity. It is about seeing through differences to find the things we all share in common. Burson added the database of Middle Eastern faces, both Arab and Jewish, after the terrorist attacks on September 11. “I have always wanted to allow people to see differently. I am a photographer. I am recording the unseen, because what we can not see is so much more interesting than what we can see, ”Burson said.
For those who missed the show, the Human Race machine will be on view at the New York Hall of Science in the Queens district full-time as of June.
1. The Human Race Machine can .| A．tell you what you would look like if you were from another ethnic group |
| B．create a digital image of your face and change it |
| C．turn your pray into reality |
| D．let people step into someone else’s skin |
| A．get nearer | B．produce |
| C．come out | D．change |
| A．she would like to change her face |
| B．she had a strange feeling |
| C．she was satisfied with what she looked like as a Middle Eastern person |
| D．she could buy the Human Race machine |
| A．it can unite the facial feather of a different ethnic group with your own |
| B．it shows that we all have something in common in spite of different races |
| C．one can pray before the machine |
| D．if you want, the machine can change your face |
| A．she wanted to show people what terrorists look like |
| B．she wanted to record what people cannot see |
| C．she wanted to be famous as a photographer |
| D．she wanted to let people see the foreign people |
【推荐2】It's clear that YouTube has taken over the modern world and has become an incredibly influential platform. YouTube has different genres that appeal to the masses. Perhaps the most interesting of all the genres is a lifestyle creator.
Ashley
Ashley is a lifestyle You Tuber whose channel is inspirational, as she shares a glimpse of her daily life, stories with her viewers, and also does some amazing home renovation series. She is always full of creative abilities, inspiring her followers. Among all her abilities she is better known as BestDressed and her fashion sense also leads to a ton of outfit ideas.
Emma Chamberlain
The wildly popular Emma Chamberlain is perhaps one of the most fun creators on YouTube, due to her humorous personality and sharp, comical editing skills. Emma’s content surrounds her life, as she became popular on the platform due to her vlogs. She is definitely a creative and authentic creator who has changed the platform for the better.
Chris Klemens
Here's Chris Klemens, a lifestyle creator with a hilarious twist, as most of his videos are about his amusing personality. Chris is a talented creator, who finds a way to include comedy into his lifestyle videos, which are usually cooking videos, daily vlogs, or fashion related. His content is wide-ranging when it comes to genre, as he doesn't necessarily fit in one box. His content is incredibly inspiring, funny, and unique.
Claudia Sulewski
Claudia’s YouTube channel focuses on lifestyle, where she mainly posts vlogs related to her daily life. Her interests revolve around fashion, interior design, and art, as she documents her relationship with all of these genres. Her editing skills create visually pleasing effects, lending inspiration to any follower who views her videos, which usually show her day-to-day life with her boyfriend, Finneas, and their adopted puppy, Peach.
1. What is Ashley most famous for?| A．Her good taste for clothes. | B．Her creative ideas. |
| C．Her ability to renovate homes. | D．Her talent for art. |
| A．They both have excellent filming skills. |
| B．They both try to include comedy in their videos. |
| C．They both have fun personality. |
| D．They both became famous for their performances. |
| A．She works in the fashion industry. |
| B．Her editing skills makes her videos pleasant to watch. |
| C．Her YouTube centers around her boyfriend. |
| D．She has a kid named Peach. |
【推荐3】Vaping can be just as damaging to your health as smoking. But the minute you kick the habit, you’ll feel a difference.
Vaping is the use of electronic cigarettes-e-cigarettes. Vaping became mainstream in the United States in the late 2000s. When e-cigarettes first hit the market, people believed they were a safer choice to tobacco cigarettes. We now know, however, that vaping, like smoking cigarettes can be quite damaging to your health-and equally addictive.
Kids and teenagers are especially attracted to vaping, thanks to attractive flavors. Vape use in high school students rose by 900 percent between 2011 and 2015.
Quitting vaping can be difficult, just like trying to stop smoking. There are some immediate, though often temporary, negative effects. The positive ones soon outpace the negative, however.
In as little as 20 minutes, your heart rate returns to normal, your blood pressure drops, and your circulation starts to normalize. Your breathing may improve, too.
Daily e-cigarette doubles a persons risk for a heart attack. If you quit, however, the risk begins to fall very quickly. Also, vaping, like cigarette smoking, can blunt your senses, reducing your ability to smell and taste. After just 48 hours without vaping, you may begin to notice your ability to taste and smell food has improved. Nicotine affects more than your brain: new research suggests nicotine can raise your blood sugar, too.
Smokers often have a troublesome cough or make a breathless sound when they breathe that many refer to as a smokers cough. Smoking even e-cigarettes can badly harm your lung health and make fighting off infections difficult. Quitting, however, will help your lungs recover. After one month, your lung capacity improves.
There will come a day when the bad habit of vaping won’t have any lasting influence on your body and your health.
1. What did Americans think of e-cigarettes?| A．They were cheaper. | B．They were fashionable. |
| C．They were less harmful. | D．They were environment-friendly. |
| A．Its taste. | B．Its price. |
| C．Its shape. | D．Its colour. |
| A．Destroy. | B．Benefit. | C．Sharp. | D．Dull |
| A．Introduce the use of e-cigarettes. |
| B．Point out how e-cigarettes harm kids. |
| C．Encourage people to refuse e-cigarettes. |
| D．Compare e-cigarettes with traditional ones. |
【推荐1】With COVID-19 outbreaks at different stages around the world, in many countries lockdowns (封城) are being carefully eased off while urging citizens to keep on practicing the social distancing rules. Singapore is trying a new way of carrying it out—a robot dog.
The government has arranged Spot, a yellow and black robotic dog made by Boston Dynamics Company, at one local park. The same robot has ever been seen dancing to hit song “Uptown Funk” before. However, 2020 is an extremely difficult year and the company is trying to assist the national coronavirus-control effort. In turn, the job has been handed over to Spot.
The four-legged robot dog patrols (巡查) the park and broadcasts a pre-recorded message to encourage visitors to observe safe distancing measures. As it walks around the park, the dog says in a female voice, “Let’s keep Singapore healthy. For your own safety and for those around you, please stand at least one meter apart. Thank you.”
Spot is one of the world’s most advanced robots and unlike wheeled robots, it is capable of going pretty much anywhere a dog can go and can walk up to three miles per hour over different areas, making it ideal for operation in public parks and gardens. Furthermore, it is remotely controlled and has cameras with 360-degree vision and analytic tools to scan the surroundings and help officials estimate the number of people gathering in the park.
For now, the project is currently set to run in a limited trial for two weeks at one park during off-peak (非高峰) hours. But if all goes well, authorities will consider expanding the program to improve enforcement (强制) of social distance throughout on Singapore.
Spot is also being used in other ways during the public health crisis beyond just patrolling a park. The government says it’s also using Spot in another capacity—at a local isolation facility where the robot helps bring medicine to patients.
1. What do we know about Spot in the passage?| A．It’s a dog-like robot that can speak. |
| B．It’s a robot that can sing a popular song. |
| C．It’s a wheeled robot that can walk anywhere. |
| D．It’s a robot newly invented during the pandemic (流行病). |
| A．It enforces people to follow the rules. |
| B．It politely tells people to keep apart. |
| C．It works day and night to patrol the park. |
| D．It warns visitors against throwing trash anywhere. |
| A．Some smart features of the robot. |
| B．The robot dog’s basic equipment. |
| C．The working condition of the robot. |
| D．The experiment process of the project. |
| A．Spot, a Dog like Robot, Walks in the Park. |
| B．A New Program is Expanding in Singapore. |
| C．A Multi-skilled Robot Goes Beyond the Park. |
| D．Singapore Leads the Top in Fighting COVID-19. |
【推荐2】A New Jersey couple and a homeless man have been accused of making up a feel﹣good story that raised more than ＄400,000 through GoFundMe.
The couple, Kate McClure and Mark D'Amico, and the man, Johnny Bobbitt Jr., face a charge of second-degree theft, Burlington County Prosecutor Scott Coffina said Thursday.
The couple said they met Bobbitt when he gave his last ＄20 to McClure, who was stranded on Interstate 95 in Philadelphia, so she could put gas in her car，then started the GoFundMe campaign as a way to thank him.
The paying-it-forward story that drove this fundraiser might seem too good to be true, Coffina said at a press conference.
Unfortunately, it was. The entire campaign was based on a lie.
After fees, the money of the campaign netted about ＄367, 000, all deposited into McClure's accounts, Coffina said. Bobbitt received ＄75,000, and within months McClure and D'Amico had wasted their share on buying a car, high-end handbags and trips, Coffina said. They also used it at casinos(赌场), he said.
Coffina stressed that while Bobbitt, a veteran (老兵), deserves thanks for his service to the country and sympathy for his situation; he was fully involved in the crime, using media to help "promote the dishonest campaign".
According to Coffina, McClure and D'Amico first met Bobbitt at an off-ramp（驶出匝道）near a casino they regularly went, at least a month before the GoFundMe campaign went live.
They went back to the spot a month later, Coffina said. D'Amico took a picture of McClure and Bobbitt that became the face of the GoFundMe campaign that they started hours later, Coffina said.
1. What's the actual purpose of the GoFundMe campaign started by the couple?| A．To express their appreciation for Bobbitt's help. |
| B．To help Bobbitt pay off his heavy debt. |
| C．To raise money for their own benefit. |
| D．To make people believe in Bobbitt's generosity. |
| A．Impossible to finish. |
| B．Unable to move. |
| C．Without any choice. |
| D．Out of service. |
| A．About ＄292, 000. |
| B．About ＄367, 000. |
| C．About ＄325, 000. |
| D．About ＄400, 000. |
| A．Pretending to be a veteran. |
| B．Robbing the couple of ＄75, 000. |
| C．Failing to serve his country. |
| D．Helping invent the story. |
【推荐3】Christian Eijkman, a Dutch doctor, left the Netherlands for the island of Java. Many people on the island had a disease called beri-beri. He was going there to try and find a cure.
At first, Eijkman thought some kind of germ (细菌) caused beri-beri. He raised some chickens. He didn’t eat them, but made experiments on them. The local people were quite surprised at that. One day he noticed that his chickens became sick when they were fed the food most Javanese ate — refined white rice (精炼米). When he fed them with unrefined rice, also known as brown rice, they recovered. Eijkman realized that he had made an important discovery — that some things in food could prevent disease. These things were named vitamins (维生素). The Javanese were not getting enough vitamins because they had actually removed the part that contains vitamins. Later, other diseases were also found to be caused by the lack of vitamins in a person’s food.
Today many people know the importance of vitamins and they make sure they have enough vitamins from the food they eat. If they don’t, they can also take vitamin pills.
1. The underlined word “cure” in Paragraph 1 probably means ______.| A．a kind of vitamin | B．a medical treatment | C．a kind of germ | D．a kind of rice |
| A．spend his holiday |
| B．find ways to grow better crops |
| C．help the Javanese with their illness |
| D．do some research about the island |
| A．To eat them. |
| B．To give the Javanese a surprise. |
| C．To carry out his experiments. |
| D．To make money by selling them. |
| A．beri-beri was caused by chickens |
| B．the Javanese didn’t like vitamins |
| C．the Javanese’s disease was caused by a kind of germ |
| D．Christian Eijkman’s experiment was successful |
