1 . If I scratch your back and you scratch mine, then we're both better off as a result — so goes the principle of reciprocity. As humans, we are familiar with the concept. But do animals also help those who help them? The answer may be yes. A paper by Dolivo and Taborsky shows that Norway rats will only give as good as they get.
In their laboratory, Dolivo and Taborsky first trained rats to pull on a stick that drew a food item within reach of a rat in a neighboring cage separated from them by wire mesh (钢丝网).
They then introduced a further treatment in which an experimental rat was placed in a cage with other caged rats on either side. On one side the rat pulled a stick that provided pieces of carrot to the rat in the central cage, while the other pulled a stick that produced banana pieces.
In the following trials the focal rat (the one in the central cage) had the opportunity to repay the other rats using the same stick tool to deliver food items.
Now, the rats had typically turned their noses up at the carrot and showed a strong preference for the more desirable banana. On the basis that the banana-providing rat should therefore be remembered as the superior partner, the authors predicted that in the test phase (阶段) the focal rat would more readily provide help for banana-offering rats than for carrot-offering rats. This proved to be the case: the rats that had provided better help in the past received greater rewards - it seemed that they were behaving reciprocally.
Dolivo and Taborsky's experiments show that rats can recall the quality of help provided and by which rat, and adjust their behavior so as to invest more time and energy in helping those that helped them. It is apparent that we shouldn't undervalue the ability of animals to engage in reciprocity.
1. What does the underlined word ''reciprocit'' in Paragraph 1 probably refer to?| A．The act of being kind to other people. | B．A cooperative exchange of favors. |
| C．A positive attitude to everything. | D．The quality of being generous. |
| A．It would find some food in its own cage. |
| B．Other rats would be able to enter its cage. |
| C．Another rat in another cage would get food. |
| D．It would be able to enter a neighboring cage. |
| A．The rats that preferred carrot pieces. |
| B．The rats that preferred banana pieces. |
| C．The rats that had provided carrot pieces. |
| D．The rats that had provided banana pieces. |
| A．Some animals may return others' help. |
| B．Norway rats have very poor memories. |
| C．It is hard to explain the ability of animals. |
| D．Rats behavior is very uncommon. |
2 . A message slick was form of ancient and nonverbal（非语言的）communication that came from Australia, particularly among aboriginal people. It was a wooden stick with designs and symbols on it. These objects were relayed by couriers（信使）among various tribes and thus functioned as a means of cross-cultural communication.
" Aboriginal" is a term that refers to those who are believed to be the first known people living in a particular place, and in this case, it is used to describe several subgroups of native Australians. Each group might have its own unique customs and language. They were often divided into tribes , so these groups needed a means to communicate. Message sticks were first invented for this purpose.
The stick itself was often made of the wood of native Australian trees. Messages were placed on the sticks using a variety of methods, including carving, painting or burning symbols onto the wood. The markings usually consisted of wordless symbols that had to be translated by the courier. The courier was thus usually a physically fit young man who had mental sharpness to properly convey message details.
Message sticks functioned as a neutral（中立的）area between tribes. Couriers were allowed to have safe passage, even if they came from an enemy land. Sometimes, the method of delivery consisted of a single courier carrying a message stick from tribe to tribe. Other methods had one tribe begin a passing process among tribes, with each tribe using its own courier to convey the message to the next tribe.
This object also has survived as part of Australian cultural celebrations. Some schools, for example, design and transport message sticks as a means of learning about the past, In addition, the term" message stick" is often used in Australian language as a reference to other communication forms such as newspapers or radio broadcasts.
1. For what purpose did aboriginal people use a message stick?| A．To learn from each other. |
| B．To show one tribe's power. |
| C．To show their designs and symbols. |
| D．To make communication across different tribes. |
| A．What " aboriginal" means. |
| B．Why message sticks were created. |
| C．What the customs of native Australians were. |
| D．How native Australians were divided into groups. |
| A．He would be let go. |
| B．He would be killed. |
| C．He would be greatly respected. |
| D．he would be driven out immediately. |
| A．'To learn aboriginal language. |
| B．'To learn about aboriginal history. |
| C．To refer to newspapers and the radio. |
| D．To communicate among themselves. |
3 . New data presented this week at the annual Associated Professional Sleep Societies (APSS) suggest that a student's preferred sleeping schedule has a lot to do with his or her grade-point average in school. In one study, researchers at the University of Pittsburg revealed that poor sleep habits among high schoolers led to lower grades, particularly in math.
It's no surprise that poor sleep habits may negatively impact academic performance. And dozens of studies have linked an increase in nightly sleep to better cognition and alertness. The new research, however, goes a step further, quantifying the impact of erratic or inadequate sleep on grades. These findings are more convincing than saying that if you get more sleep, you'll feel better," says Jennifer Cousins, a lead researcher of the study.
The study involved data from 56 adolescents (34 female) between the ages of 14 and 18 years. They were asked to fill out sleep diaries for one week and wear a special activity monitor on their wrists, which recorded when the students were asleep or awake. Overall, teens with poor sleep habits received lower grades than students who stuck with a more regular sleep routine.
Interestingly, Cousins also found that different sleep habits had different effects on the students' school performance：those who woke up more often during the night did worse in math, for example, while those who slept peacefully through the night tended to get better grades in English.
These findings bring up new questions about teasing out（探讨）the details of what is important about sleep that impacts learning," says Cousins. "Does more sleep improve our ability to deal with abstract concepts found in math, or does sleep quality increase creativity? We don't know the answers, and don't want to draw those conclusions yet. But this helps us understand more about how sleep helps the things we do in daily life. "
Authors of the study point out that the results provide overwhelming evidence of the importance of sleep during a period of development that is critical for adolescents and recommend sleep education as a prevention tool to help increase awareness of the importance of sleep and of the negative consequences of poor sleep.
1. The underlined word "erratic" in the second paragraph probably means______.| A．adequate | B．different |
| C．stable | D．irregular |
| A．lower grades in math are related to more awakenings at night |
| B．the longer you sleep, the better your grades in English will be |
| C．the findings will cause new insoluble problems about sleeping and learning |
| D．different sleep habits have similar effects on students' learning |
| A．People should understand the importance of sleep for students. |
| B．Whether greater sleep quality help increase students' creativity is not known yet. |
| C．Students' grades mainly depend on their sleep quality. |
| D．The study helps researchers understand how sleep affects learning. |
| A．The More Sleep, the Better Cognition |
| B．The Poorer Sleep Habits, the Lower Grades |
| C．The More Sleep, the Better You Will Feel |
| D．The More Peacefully You Sleep, the Higher Grades You Will Get |
4 . Mom was right! If you say "thank you" for even the smallest gift or slightest show of kindness, you'll feel as happy as Larry.
Gratitude, says Robert A. Emmons, a professor of psychology at the University of California, Davis, is an important element of happiness. In his recent book, Thanks!Emmons uses the first major study on gratitude to prove mom's point. In acknowledging and developing this much-ignored expression of thankfulness, he explains how people have benefited-even improved their health.
Expressing gratitude shouldn't be a reaction； it should be a state of mind. To feel grateful when life is a breeze and you have more than you need is easy. To feel grateful in time of crisis-anger, hatred and bitterness-is easier. Also, too many people are aware of life's blessings only after these are lost.
It's crisis and chaos-danger, disease, disability and death-that bring many individuals to realize just how dependent they are on others. Yet it's the way each of us begins life and ends it. It's too bad that so many people waste those decades in between labouring under the illusion that they are self-sufficient, says Emmons.
The abundance of voices expressing gratitude from his studies of individuals with chronic health problems is many. But Emmons goes beyond his groundbreaking" science to make his case for gratitude by including the inspirational writings of philosophers, novelists and saints, as well as the beliefs of various religions and their respective scriptures. Taken together, these observations are summed up quite nicely by famous humanist Albert Schweitzer, who said the secret of life is "giving thanks for everything".
To enable and embrace gratitude, Emmons encourages the readers of Thanks! to keep a gratitude diary. He even provides easy-to-follow directions on how to practice and develop gratitude.
I'm not a reader or advocate of self-help books, but I am thankful for the reference I found in a newspaper article to the research Emmons was conducting on gratitude involving organ donors and recipients. The chance discovery led me to this book.
Mom implied that kindness seems to find its way back to the giver because life really is all about giving, receiving and repaying. So I'll pay attention to her Professional advice and say: Thank you, Professor Emmons.
1. What is the text mainly discussed?| A．There are many ways of being thankful. | B．Mom is great for her being thankful. |
| C．Gratitude is important to happiness. | D．Being thankful will keep you fit forever. |
| A．Professor Emmons supports mom's study on psychology. |
| B．mom is as great a psychologist as Professor Emmons. |
| C．Professor Emmons is a famous psychologist. |
| D．mom is right about her viewpoint on gratitude. |
| A．It is enough to thank others orally. |
| B．Whether you are thankful is always up to you. |
| C．Remember to be thankful anytime and anywhere. |
| D．It is easier to be thankful for yourself than for others. |
| A．helpful | B．unreasonable |
| C．puzzling | D．one-sided |
5 . It is hard, it hurts —and yet more than two million of us in the UK run at least once a week.
Of course, some people run to lose weight, or to get fit, and these are great reasons. Running is also easy to do, it's cheap, and you can do it when you want. All these factors certainly contribute to the fact that running is one of the most popular sports in the UK.
But for many of those two million runners, the real reason we head out to beat the roads until our legs hurt is more intangible (无形的) than weight loss or fitness.
Many runners become interested in times. They try to break the 40-minute barrier for the 10K, or run under four hours for the marathon. Yet, really, these times are almost meaningless. And as soon as they are achieved, another target is thrown out almost immediately.
The times are only the carrots we put in front of ourselves. But why do we put them there in the first place? Nobody ever gives a wise answer Deep down, we all know the answer.
Running brings us joy. Watch small children when they are excited, at play, and mostly they can't stop running. There's a great moment inThe Catcher in the Ryewhen Holden Caulfield, caught in the uneasy space between childhood and adulthood, is walking across his school grounds one evening and he suddenly starts to run. “I don't ever know what I was running for一I guess I just felt like it,” he says.
This will to run is born. In fact, humans may well have evolved (进化) the way we did because of our ability to run. As children, and even adolescents, we can respond to this natural call to run whenever the feeling takes us.
As we run, we begin to sense that childish joy, which is born to live a wilder existence. As we run, the layers of responsibility and identity we have gathered in our lives, father, mother, lawyer, teacher, all fall away, leaving us with the raw human being.
If we push on, running harder, deeper into the loneliness, further away from the world and the structure of our lives, we begin to feel strangely excited, separated yet at the same time connected, to ourselves. With nothing but our own two legs moving us, we begin to get a sense of who, or what, we really are. After a long run, everything seems right in the world. Everything is at peace. To experiencethisis a powerful feeling, strong enough to have us coming back, again and again, for more.
1. Why does the author think setting time goals is almost meaningless?
| A．Because those time goals can' t be achieved. |
| B．Because those time goals can be achieved easily |
| C．Because people will be very proud once the time goals are achieved. |
| D．Because there will always be a new time goal once the former one is achieved. |
| A．challenging ourselves | B．running away from responsibility |
| C．losing weight and keeping fit | D．bringing us joy and peace in mind |
| A．Uncertain. | B．Doubtful. |
| C．Supportive. | D．Puzzled. |
| A．breaking the 40 -minute barrier for the 10K. |
| B．running under four hours for the Marathon. |
| C．feeling separated from the world after running |
| D．feeling everything is right after a long run. |
| A．Running to Keep Fit | B．Running to Break Records |
| C．Running to Be the Real You | D．Running to Become an Adult |
6 . Before birth,babies can tell the difference between loud sounds and voices.They can even distinguish their mother’s voice from that of a female stranger.But when it comes to embryonic learning（胎教），birds could rule the roost.As recently reported in TheAuk:Ornithological Adrances,some mother birds may teach their young to sing even before they hatch(孵化)。New-born chicks can then imitate their mom’s call within a few days of enering the world.
This educational method was first observed in 2012 by Sonia Kieindorfer,a biologist at Flinders University in South Australia,and her collcagues.Femake Australian superb fairy wrens were found to repeat one sound over and over again while hatching their eggs,When the eggs were hatched,the baby birds made the similar chirp to their mothers—asound that served as their regular “feed me!”call.
To find out if the special quality was more widespread in birds,the researchers sought the red-backed fairy wren,another species of Australian songbird.Firstthey collected sound datd from 67 nests in four sites in Queenslang before and after hatching,Then they identified begging calls by analyzing the order and numberof notes.A computer analysis blindly compared calls produced by mothers and chicks,ranking them by similarity.
It turns out that baby red-backed fairy wrens also emerge chirping like their moms. And the more frequently mothers had called to their eggs,the more similar were the babies’ begging calls. In addition,the team set up a separate experiment that suggested that the baby birds that most closely imitated their mom’s voice were rewarded with the most food.
This observation hints that effective embryonic learning could signal neurological(神经系统的)strengths of children toparents.An evolutionary inference can then be drawn.”As a parent,do you investin quality children,or do you invest in children that are in need?”Kleindorfer asks.”Our results suggest that they might be going for quality.”
Before birth,babies can tell the difference between loud sounds and voices.They can even distinguish their mother’s voice from that of a female stranger.But when it comes to embryonic learning（胎教），birds could rule the roost.As recently reported in TheAuk:Ornithological Adrances,some mother birds may teach their young to sing even before they hatch(孵化)。New-born chicks can then imitate their mom’s call within a few days of enering the world.
This educational method was first observed in 2012 by Sonia Kieindorfer,a biologist at Flinders University in South Australia,and her collcagues.Female Australian superb fairy wrens were found to repeat one sound over and over again while hatching their eggs,When the eggs were hatched,the baby birds made the similar chirp to their mothers—a sound that served as their regular “feed me!”call.
To find out if the special quality was more widespread in birds,the researchers sought the red-backed fairy wren,another species of Australian songbird.First they collected sound data from 67 nests in four sites in Queenslang before and after hatching,Then they identified begging calls by analyzing the order and number of notes.A computer analysis blindly compared calls produced by mothers and chicks,ranking them by similarity.
It turns out that baby red-backed fairy wrens also emerge chirping like their moms. And the more frequently mothers had called to their eggs,the more similar were the babies’ begging calls. In addition,the team set up a separate experiment that suggested that the babybirds that most closely imitated their mom’s voice were rewarded with the most food.
This observation hints that effective embryonic learning could signal neurological(神经系统的)strengths of children to parents.An evolutionary inference can then be drawn.”As a parent,do you investin quality children,or do you invest in children that are in need?”Kleindorferasks.”Our results suggest that they might be going for quality.”Before birth,babies can tell the difference between loud sounds and voices.They can even distinguish their mother’s voice from that of a female stranger.But when it comes to embryonic learning（胎教），birds could rule the roost.As recently reported in TheAuk:Ornithological Adrances,some mother birds may teach their young to sing even before they hatch(孵化)。New-born chicks can then imitate their mom’s call within a few days of enering the world.
This educational method was first observed in 2012 by Sonia Kieindorfer,a biologist at Flinders University in South Australia,and her collcagues.Female Australian superb fairy wrens were found to repeat one sound over and over again while hatching their eggs,When the eggs were hatched,the baby birds made the similar chirp to their mothers—a sound that served as their regular “feed me!”call.
To find out if the special quality was more widespread in birds,the researchers sought the red-backed fairy wren,another species of Australian songbird.First they collected sound data from 67 nests in four sites in Queenslang before and after hatching,Then they identified begging calls by analyzing the order and number of notes.A computer analysis blindly compared calls produced by mothers and chicks,ranking them by similarity.
It turns out that baby red-backed fairy wrens also emerge chirping like their moms. And the more frequently mothers had called to their eggs,the more similar were the babies’ begging calls. In addition,the team set up a separate experiment that suggested that the babybirds that most closely imitated their mom’s voice were rewarded with the most food.
This observation hints that effective embryonic learning could signal neurological(神经系统的)strengths of children to parents.An evolutionary inference can then be drawn.”As a parent,do you investin quality children,or do you invest in children that are in need?”Kleindorferasks.”Our results suggest that they might be going for quality.”
Before birth,babies can tell the difference between loud sounds and voices.They can even distinguish their mother’s voice from that of a female stranger.But when it comes to embryonic learning（胎教），birds could rule the roost.As recently reported in TheAuk:Ornithological Adrances,some mother birds may teach their young to sing even before they hatch(孵化)。New-born chicks can then imitate their mom’s call within a few days of enering the world.
This educational method was first observed in 2012 by Sonia Kieindorfer,a biologist at Flinders University in South Australia,and her collcagues.Female Australian superb fairy wrens were found to repeat one sound over and over again while hatching their eggs,When the eggs were hatched,the baby birds made the similar chirp to their mothers—a sound that served as their regular “feed me!”call.
To find out if the special quality was more widespread in birds,the researchers sought the red-backed fairy wren,another species of Australian songbird.First they collected sound data from 67 nests in four sites in Queenslang before and after hatching,Then they identified begging calls by analyzing the order and number of notes.A computer analysis blindly compared calls produced by mothers and chicks,ranking them by similarity.
It turns out that baby red-backed fairy wrens also emerge chirping like their moms. And the more frequently mothers had called to their eggs,the more similar were the babies’ begging calls. In addition,the team set up a separate experiment that suggested that the babybirds that most closely imitated their mom’s voice were rewarded with the most food.
This observation hints that effective embryonic learning could signal neurological(神经系统的)strengths of children to parents.An evolutionary inference can then be drawn.”As a parent,do you investin quality children,or do you invest in children that are in need?”Kleindorferasks.”Our results suggest that they might be going for quality.”
1. The underlined phrase in Paragraph 1 means“ ”.| A．be the worst | B．be the best |
| C．be the as bad | D．be just as good |
| A．Similarities between the calls moms and chicks. |
| B．The observation of fairywrens across Australia. |
| C．The data collected fromQueensland’slocals. |
| D．Controlled experiments on wrens and other birds. |
| A．can receive quality signals | B．are in need of training |
| C．fit the environment better | D．make the loudest call |
7 . One of the greatest killers in the Western world is heart disease.The death rate( 率) from the disease has been increasing at an alarming speed for the past thirty years.Today in Britain,for example,about four hundred people a day die of heart disease.Medical experts know that people can reduce their chances of getting heart disease by exercising regularly,by not smoking,by changing their diets,and by paying more attention to reducing stress(压力) in their work.
However,Western health-care systems are still not paying enough attention to the prevention of the disease.There is a need for more programs to educate the public about the causes and prevention of heart disease.Instead of supporting such programs,however,the U.S.health-care system is spending large sums of money on the surgical( 外 科 的 ) treatment of the disease after it develops.This emphasis( 强 调 ) on treatment clearly has something to do with the technological advances that have taken place in the past ten to fifteen years.In this time,modern technology has enabled doctors to develop new surgical techniques.Many operations that were considered impossible or too risky(有风险的) a few years ago are now performed every day in U.S.hospitals.The result has been a huge increase in heart surgery.
Although there is no doubt that heart surgery can help a large number of people,some people point out that the emphasis on the surgical treatment of the disease has three clear disadvantages.First,it attracts interest and money away from the question of prevention.Second,it causes the costs of general hospital care to rise.After hospitals buy the expensive equipment that is necessary for modern heart surgery,they must try to recover the money they have spent.To do this,they raise costs for all their patients,not just those patients whose treatment requires the equipment.The third disadvantage is that doctors are encouraged to perform surgery—even on patients for whom an operation is unnecessary—because the equipment and expert skills are there.A government office recently stated that major heart surgery was often performed even though its chances of success were low.In one type of heart surgery,for example,only 15 percent of patients improved their conditions after the surgery.However,more than 100,000 of these operations are performed in the United States every year.
1. What effect has modern technology had on medicine?| A．It has reduced the costs of medical treatment. |
| B．It hasn’t helped save any patients. |
| C．It has encouraged doctors to do more heart surgeries. |
| D．It has helped educate people about the prevention of heart disease. |
| A．to help patients recover |
| B．to increase the number of heart surgeries |
| C．to get back the money spent on the equipment |
| D．to buy new equipment for the treatment of heart disease |
| A．more money should be spent on the prevention of heart disease |
| B．heart surgery has helped most patients improve their conditions |
| C．modern technology has made heart surgery more risky than before |
| D．the public have known a great deal about the causes of heart disease |
| A．The Greatest Killer in the West |
| B．Heart Disease:Treat or Prevent |
| C．Old Technology and Heart Surgery |
| D．Heart Surgery:Advantages |
8 . NASA has a new job listing, and it’s no joke. The US space agency (机构) is looking for a “joker” to join their planned mission (任务) to Mars.
A mission to Mars is no laughing matter. On average, the red planet is 140 million miles (225 million kilometers) away from Earth. A trip there would take around eight months in a small spacecraft. And Mars has a communications delay (延迟) of 20 minutes. This means that astronauts will have to wait 20 minutes for a reply, when an emergency happens.
“When you’re living with others in a confined space for a long period of time, such as on a mission to Mars, problems are likely to occur,” Jeffrey Johnson, a scientist at the University of Florida, told The Guardian.
This is probably why NASA wants an astronaut with a sense of humor. “These are people that have the ability to pull everyone together,” Johnson said.
In stressful situations, perhaps humor is a way to know we aren’t alone. By laughing together, we share our stress. Then we can focus on our jobs instead of just worrying.
There are other examples of team “clowns”. One example is the journey to the South Pole (南极) led by Norwegian explorer Roald Amundsen. It was a difficult journey, full of danger. Adolf Lindstrom, a cook at Amundsen’s team, was a “clown”. He made people laugh through the whole journey. Amundsen later wrote that Lindstrom was the most valuable member of the team.
But if you’re hoping that your favorite TV comedian (喜剧演员) will fly to Mars, that probably won’t happen.
“Being funny won’t be enough to land somebody the job,” Johnson said. “They also need to be an excellent scientist and engineer.”
Besides, they must be in top physical condition.
1. What is NASA’s new job listing?| A．A funny engineer. | B．A talented clown. |
| C．A good cook. | D．A popular comedian. |
| A．a crowded space | B．an empty space |
| C．an open space | D．a small space |
| A．It can stop them from feeling worried. |
| B．It can encourage teamwork on a mission. |
| C．It can help them feel less homesick. |
| D．It can help them know themselves better. |
| A．A New Job Listing of NASA |
| B．Humorous Astronauts in NASA |
| C．Keeping the Spirits Up |
| D．A mission to Mars |
9 . Heart disease is one of the major killers in the world today. Many who suffer from it must have heart transplants (移植). However, it’s difficult to get a suitable heart donation, and even if a patient survives the wait, his or her body often rejects (排斥) the heart.
But there is now new hope for sufferers of heart disease. According to a study published in the journal Advanced Science, researchers from Israel’s Tel Aviv University printed a 3D human heart on April 15.
“This is the first time anyone anywhere has successfully engineered and printed an entire heart,” professor Tal Dvir told CNN.
Unlike the previous 3D-printed heart structure, the new heart is complete with cells, blood vessels (血管), chambers (心室) and other structures a heart needs to function normally. But scientists still have more to figure out before the 3D-printed heart can be fitted into the body. For one thing, the experimental heart is only the size of a thumb (拇指). And, although it can contract (收缩) like a muscle, it cannot pump out blood like a real one. At present, the heart prototype (样品) is like a tiny airplane that has all of the right parts, but can’t fly.
However, the development is still regarded as a major breakthrough in medicine.
In the experiment, the researchers turned human fat tissue (脂肪组织) into human heart tissue with stem cell (干细胞) technology. The tissue was then turned into “bio-ink” for a 3D printer to ensure that tissue in the heart came from the patients themselves. So ideally, if it were to be placed in the body of someone in need of a transplant, there would be less risk of organ rejection.
“Patients will no longer have to wait for transplants or take medications to prevent their rejection,” researchers told USA Today. “Instead, the needed heart will be printed, fully personalized (个性化的) for every patient.”
But the scientists think that 3D printing can be used to create other human organs. They foresee a time when the 3D printing of organs will be an everyday medical practice.
“Maybe, in 10 years, there will be organ printers in the finest hospitals around the world and these procedures will be conducted routinely,” Dvir said.
1. Why is the 3D-printed heart important?| A．It will be used on a patient. |
| B．It is the first 3D-printed heart. |
| C．It will replace a heart donation. |
| D．It has a complete heart structure. |
| A．They cost too much. | B．They are too small. |
| C．They can’t contract. | D．They are hard to produce. |
| A．It would be made with stem cell technology. |
| B．It would be made from human fat tissue. |
| C．It would come from a patient’s body. |
| D．It would be printed according to the patient’s condition. |
| A．Confident. | B．Doubtful. |
| C．Worried. | D．Confused. |
10 . The Consumer Technology Association, formerly called The International Consumer Electronics Show, or CES, believes about 170, 000 people will attend the show. About one-third of them are reported to come from countries besides the United States.
More than 4, 000 businesses will show products used through the Internet such as gaming, self-driving cars, artificial intelligence（人工智能）and robotics. One of the biggest stars at CES this year is the voice-controlled digital （数字的）assistant. While the technology is not new, many companies will show off the latest digital assistants.
Equipment controlled by digital assistants, especially those turned on by voice, were already big sellers in 2017. This year, Google, Amazon and Apple are expected to release even more products to keep up with the rising demand.
Digital assistants are powered by artificial intelligence and machine learning technology. They are designed to learn users' preferences over time and then “think" and act on their own. Some of the biggest developments in technology have come in the area of home automation （自 动化）. Amazon Echo, Google Home, Apple's Home Pod and Microsoft's Cortana are a few examples of voice-controlled equipment. All include smart speakers that “talk" to users inside the house and can perform operations.
Experts with the Consumer Technology Association say sales of smart speakers are expected to nearly double in 2019.
The Internet-linked products can play music or find information when asked questions. They can also control equipment such as lighting, cameras, televisions and temperature controllers. Among new “smart" home products to be released at the CES are voice-controlled washing machines, refrigerators, showers and toilets. There is also much new physical fitness and health-related equipment on show. Some are designed to help people create the best personal fitness plans to reach their goals. Wearable health equipment is used to study and measure body conditions, while others help recognize signs of disease.
1. What will be shown at CES?| A．Books about robots. |
| B．International fashion. |
| C．Schools' teaching art. |
| D．Equipment related with the Internet. |
| A．To create music. |
| B．To treat all kinds of diseases. |
| C．To meet the increasing needs. |
| D．To make experiments in space. |
| A．By fax. |
| B．By voice. |
| C．By email. |
| D．By body language. |
| A．Art. |
| B．Health. |
| C．Education. |
| D．Technology. |
