A recent study by a team of researchers from Canada has uncovered that birds living in cities are not just better at problem solving and more skilled in tasks than those in the countryside: they also have stronger immune（有免疫力的）systems !
The research, headed by Audet, a Ph. D. student at a university, examined the cognitive （认知的）abilities of city birds with those of their country cousins. The team did their study in Barbados because it needs a broad range of situations: from crowded modern cities to the countryside. They began by catching some birds from various parts of the Caribbean Island. The birds were then given several tasks. Some tested their associative learning skills while others were to observe how creative they were at problem-solving. While country birds are also much braver, the city birds appeared to be more careful when facing unfamiliar things.
The results did not surprise the researchers. After all, birds living in cities and towns face many more challenges and dangers than those that live in the country. But as it turns out, the city birds proved to have better immunity and are therefore more resistant （抵抗的）to diseases than those living in the countryside. While additional studies need to be done to see if this is true for all city birds, there is no reason to believe that the results would be any different.
Though this is the first time researchers have compared the cognitive abilities of birds living in different conditions, it is not the first study to examine the differences between city and country birds. Previous research has shown that blackbirds in cites are similarly more careful than country blackbirds, and that sparrows and blackbirds living in cities sing at a higher frequency to be heard over city noise and to make up for sound distortions（失真）caused by tall buildings. If only birds knew the advantages of living among humans, maybe more would move to cities!
1. How are city birds different from country birds according to the research?| A．City birds have a weaker immune system because of air pollution. |
| B．City birds are braver when facing unfamiliar things or situations. |
| C．Country birds are less skilled at jobs requiring creation and skills. |
| D．Country birds have a wider range of challenges to survive. |
| A．Country birds can be taught the advantage of living in cities. |
| B．City birds are more resistant to diseases than country birds. |
| C．City birds are more likely to get sick than country birds. |
| D．Country birds are more careful in dangerous situations. |
| A．There're more dangers in cities for them. |
| B．The birds live far away from each other. |
| C．There are a wider range of situations. |
| D．There's too much noise in the city. |
| A．Research into birds' immune system and learning power. |
| B．City birds are smarter and healthier than country birds. |
| C．What a PhD. student has done has surprised the world. |
| D．The necessity and ways to move country birds to cities. |
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【推荐1】“We thought dogs would behave like children under age 5, but now we guess that perhaps dogs can understand when someone is dishonest,” says Huber at the University of Vienna in Austria. “Maybe they think, ‘This person has the same knowledge as me, but is giving me the wrong information.’ It’s possible they could see that as intentionally misleading, which is lying.”
Once that trust was established, the team had the dogs witness another person move the food from the first to the second bowl. The communicators were either in the room, and also witnessed the switch, or were briefly absent and so apparently unaware that the food had been switched. In either case, the communicators would later recommend the first bowl, which was now empty.
In previous versions of this experiment with children under age 5, the participants reacted in particular ways. They would typically ignore the communicator who gave honest but misleading advice on where the food was. However, if the communicator had been in the room and witnessed the switch, but still recommended the first (now empty) bowl, young children were actually much more likely to follow the communicator’s knowingly misleading suggestion.
This may be because the children and non-human primates (灵长类) trusted the communicator over the evidence of their own eyes, says Huber.
The dogs in the new experiment, however, weren’t so trusting of lying communicators, much to the researchers’ surprise, says Huber. Half of the dogs would follow the communicator’s misleading advice if the communicator hadn’t witnessed the food switch. But about two-thirds of dogs ignored the communicator who had witnessed the food switch and still recommended the now-empty bowl. These dogs simply went to the bowl filled with food instead. “They did not rely on the communicator anymore,” says Huber.
1. What do Huber’s words in paragraph 1 imply?| A．Dogs won’t believe people any longer. |
| B．Dogs can be trained to act like children. |
| C．Dogs can understand everything humans mean. |
| D．Dogs are a lot cleverer than we thought. |
| A．To draw a conclusion. | B．To sum up the reason. |
| C．To make a comparison. | D．To lead in a new experiment. |
| A．The one who moved the food. |
| B．The one who didn’t see the food switch. |
| C．The one who moved the food and recommended the wrong bowl. |
| D．The one who saw the food switch and recommended the wrong bowl. |
| A．Dogs can sometimes tell when people are lying. |
| B．Dogs are cleverer than children under age 5. |
| C．We can train dogs to find food in different ways. |
| D．We should be honest like dogs. |
【推荐2】Many owners dream of taking a walk with their dog without a rope and those dreams are not impossible.
Tie a collar around the dog’s neck and attach a rope to the collar. Even though your initial goal is to train the dog to walk off-rope, starting his training with a rope keeps him under control.
Teach the dog a “watch me” command. It teaches the dog to focus on your face and watch your eyes, which is important to keeping the dog’s attention when you switch to off-rope work. Call the dog’s name and hold a treat close to his nose.
Encourage the dog to walk close by your side. Keep a treat in your left hand, holding it just out of his reach. Tell him “Sit down” and step off, taking a few quick steps forward.
| A．Give the order and bring the treat toward your eyes. |
| B．You must tie a rope to the collar around the dog’s neck. |
| C．What you need to do is use a firm on-rope training first. |
| D．If he always focuses on the training, give him plenty of praise. |
| E．Always be ready to tie the rope onto his collar if the need arises. |
| F．Speak in an enthusiastic voice and hold the treat within his reach. |
| G．Repeat the on-rope work with the dog off-rope until he performs perfectly. |
【推荐3】Cloning has always been with us and is here to stay. It is a way of making an exact copy of another animal or plant. It happens in plants when gardeners take cuttings from growing plants to make new ones. It also happens in animals when twins identical in sex and appearance are produced from the same original egg. The fact is that these are both examples of natural clones.
Cloning has two major uses. Firstly, gardeners use it all the time to produce commercial quantities of plants. Secondly, it is valuable for research on new plant species and for medical research on animals. Cloning plants is straightforward while cloning animals is very complicated. It is a difficult task to undertake. Many attempts to clone mammals failed. But at last the determination and patience of the scientists paid off in 1996 with a breakthrough — the cloning of Dolly the sheep.
The procedure works like this:
Female sheep A provides an egg cell.
The nucleus is removed from the egg cell.
The egg cell is ready for a new nucleus.
Female sheep B provides a somatic cell for the clone. The nucleus of this cell contains all the genes needed to produce a new sheep.
The nucleus is taken out of the somatic cell.
The nucleus from sheep B and the egg cell from sheep A are joined using electricity.
The cell divides and grows into an embryo.
The embryo is put into female sheep C, who becomes the carrier of the clone.
The lamb is the clone of the donated cell from sheep B which provided the nucleus.
On the one hand, the whole scientific world followed the progress of the first successful clone, Dolly the sheep. The fact that she seemed to develop normally was very encouraging. Then came the disturbing news that Dolly had become seriously ill. Cloning scientists were cast down to find that Dolly’s illnesses were more appropriate to a much older animal. Altogether Dolly lived six and a half years, half the length of the life of the original sheep. Sadly the same arbitrary fate affected other species, such as cloned mice. The questions that concerned all scientists were: “Would this be a major difficulty for all cloned animals? Would it happen forever? Could it be solved if corrections were made in their research procedure?”
On the other hand, Dolly’s appearance raised a storm of objections and had a great impact on the media and public imagination. It became controversial. It suddenly opened everybody’s eyes to the possibility of using cloning to cure serious illnesses and even to produce human beings.
Although at present human egg cells and embryos needed for cloning research are difficult to obtain, newspapers wrote of evil leaders hoping to clone themselves to attain their ambitions. Religious leaders also raised moral questions. Governments became nervous and more conservative. Some began to reform their legal systems and forbade research into human cloning, but other countries like China and the UK, continued to accumulate evidence of the abundant medical aid that cloning could provide. However, scientists still wonder whether cloning will help or harm us and where it is leading us.
1. Which one is the best statement about the uses of cloning?| A．To produce commercial quantities of plants. | B．To research on new plant species. |
| C．To do medical research on animals. | D．All of the above. |
| A．is usually as healthy as the original one. |
| B．usually lives as long as the original one. |
| C．usually lives longer than the original one. |
| D．usually lives shorter than the original one. |
| A．Female sheep A is more important than the female sheep B and C. |
| B．Female sheep C provides a somatic cell. |
| C．The joined cell divides and grows straight into the lamb. |
| D．Female sheep A’s egg cell whose nucleus is taken out is ready for the nucleus of a somatic cell from female sheep B. |
| A．Because it is a difficult task to undertake in some countries. |
| B．Because it is difficult to get the human eggs and embryos. |
| C．Cloning is controversial in some countries for moral and religious reasons. |
| D．Because some countries forbade research into cloning. |
| A．Impartial | B．Positive | C．Negative | D．Indifferent(漠不关心的) |
【推荐1】Plants go into a state of complete “panic” when it rains, according to surprised scientists. This response is so unusual because plants obviously need water to live. The researchers think that the “panic” response is due to the fact that moisture creates the number one way for diseases to spread in vegetation.
Biochemist Harvey Millar from the University of Western Australia explained: “When a raindrop splashes across a leaf, tiny droplets of water go in all directions. These droplets can contain bacteria, or viruses. A single droplet can spread these up to 10 meters to surrounding plants.” The longer a leaf is wet, the greater the chance that a disease can take hold.
So this is why the researchers think plants react to rain like humans would react to someone sneezing on them. They conducted an experiment in which they mimicked rain with a spray bottle and noticed rapid microscopic reactions from the plants that are invisible to the human eye. After the first 10 minutes of artificial raining, over 700 genes in the plants were said to respond in a panic-like manner and most of them continued to do so for around 15 minutes. In this time chemical reactions like how the plant creates proteins and its hormone balance were affected.
A single touch of water activated an immediate response from plants. The reactions created warning signals that travelled from leaf to leaf and resulted in the plant producing a range of protective measures. Plants that were repeatedly watered eventually suffered from stunted growth and delayed flowering.
Interestingly, the plants were also found to be communicating their “fears” with nearby vegetation. They did this by producing airborne chemicals that can be picked up by other plants and inform them what’s going on and how they’re coping. Millar said: “If a plant’s neighbors have their defence systems turned on, they are less likely to spread disease, so it’s in their best interest for plants to spread the warning to nearby plants.”
1. Paragraph 2 mainly talks about ________.| A．how droplets spread bacteria or viruses |
| B．why plants get into a “panic” when it rains |
| C．how tiny drops of water go in all directions |
| D．that longer leaves can take hold of more diseases |
| A．poured | B．fetched |
| C．contained | D．imitated |
| A．To question the ideas mentioned above. |
| B．To introduce a new topic for discussion. |
| C．To offer additional topic-related information. |
| D．To compare it with previous experiments. |
| A．Plants respond to water slowly. |
| B．Plants shut their defence systems when it rains. |
| C．Plants only communicate within their own species. |
| D．Plants may not grow well when watered too frequently. |
【推荐2】Technology usually draws us away from nature. “But now technology is offering us a chance to listen to non-humans in powerful ways, restarting our connection to the natural world,” wrote Professor Karen Bakker in her new book, The Sounds of Life: How Digital Technology Is Bringing Us Closer to the Worlds of Animals and Plants.
All around the animal kingdom, there are sounds that we struggle to pick up and interpret. Elephants, for example, communicate with each other using infrasound, a sound frequency far below our human hearing range. Corals (珊瑚虫) in the ocean also communicate with each other through sound waves, with one purpose being to attract baby corals to areas where they can successfully grow. This is a shocking fact as corals don’t have any ears! Scientists have placed listening devices (装置) in these environments to pick up sounds humans are normally unable to detect.
After the sounds are recorded, AI is then able to determine their meanings, according to the news website Vox. There are now whole databases of whale songs and honeybee dances. Bakker wrote that one day this information could be turned into “a zoological version of Google Translate”.
One animal language Bakker wrote about is that of the elephant. She explained how elephants “have a different signal for honeybees, which is a threat, and a different signal for humans” in an interview with Vox. “Moreover, they distinguish between threatening humans and non-threatening humans,” she said.
This technology can not only understand the animals, but also communicate back to them. For example, bees use dances to communicate to their fellows where to go in search of nectar (花蜜). A research team in Germany, therefore, plugged the bee language AI database system into a robot bee, allowing the robot to create a dance routine that can tell the bees which direction to move, Vox reported. In the past language creation was limited to mainly apes (类人猿), with there being many examples of chimpanzees having been taught sign language to communicate with humans, but this new technology now allows humans to socialize with different animals throughout the animal kingdom.
1. Why is Karen Bakker’s new book mentioned?| A．To introduce the topic. |
| B．To promote her new book. |
| C．To ask readers to get close to nature. |
| D．To show the convenience of technology. |
| A．They have no ears and cannot pick up sound waves. |
| B．They talk through whistling sounds with baby corals. |
| C．They communicate through sound waves like elephants. |
| D．They use sound waves to help baby corals build their homes. |
| A．Helping bees search for nectar. |
| B．Directing bees’ move through dance. |
| C．Learning about the sign language of bees. |
| D．Collecting more information about bee dances. |
| A．Learning animals’ sign language becomes easier. |
| B．It’s possible for humans to talk to animals via AI. |
| C．We can communicate with animals in the usual way. |
| D．It’s quite necessary for humans to socialize with animals. |
【推荐3】A simple gesture can be formed into a child’s memory so quickly that it will cause the child to give a false answer to a question accompanied by that gesture. A new finding suggests that parents, social workers, psychologists and lawyers should be careful with their hands as well as their words.
Gestures can be as informative as speech, but hand gestures are so common that we rarely notice we’re using them.
While the recall of both adults and children are easy to react to suggestion, the memories of children are known to be particularly influenced, said lead researcher Sara Broaders of Northwestern University. Kids are used to looking to adults to tell events for them and can be misled even if not intentionally(故意地).
Previous research, for example, has shown that detail-loaded questions often cause false answers; when asked, say “Did you drink juice at the picnic?”, the child is likely to say “yes” even if no juice had been available. It is not that the child is consciously lying, but rather the detail is quickly formed into his or her memory.
To avoid this problem, social workers have long been advised to ask children only open-ended questions, such as “What did you have at the picnic?” But an open-ended question paired with a gesture, briefly meaning a juice box, is treated like a detailed question. That is, children become likely to answer falsely.
And it isn’t just a few kids: 77% of children gave at least one piece of false information when a detail was suggested by an ordinary gesture. Gestures may also become more popular when talking with non-fluent language users, such as little kids, Broaders said as hand movements can impart meaning of unfamiliar words and phrases. “It certainly seems reasonable that adults would gesture more with children.”
In general, Broaders advises parents and other adults to “Try to be aware of your hands when questioning a child about an event. Otherwise, you might be getting answers that don’t reflect what actually happened.”
1. What do we know about gestures according to the text?| A．They have a certain effect on children. | B．They are rarely used by people. |
| C．They have no function at all. | D．They are often used by social workers. |
| A．These gestures are very attractive. | B．Their memories are affected easily. |
| C．Children are easy to tell lies. | D．These gestures are used frequently. |
| A．Separate. | B．Tell apart. | C．Confuse. | D．Pass on. |
| A．Gestures—a Useful Way of Education. | B．Gestures Can Mislead Children. |
| C．Gestures Mean Adult’s Directions. | D．Gestures Affect Children Much. |
【推荐1】Chinese athletes were highlighted by a series of inspirational wins in the International Ski Federation’s World Cup circuit recently. China’s Gu Ailing, a Chinese freestyle talent, made history by becoming the first ever back-to-back freeski World Cup winner in two different events at the same venue after claiming the slopestyle title in Calgary, Canada, on Feb.15, 2020. The day before, Gu had stormed to her first Cup gold in the halfpipe competition.
Gu again thrilled the crowds on Feb.15 in the slopestyle with another impressive display of technical riding, landing a string of difficult tricks, including a massive right 900° twist with a tail grab in her second run that earned her 89.18 points to dominate the 18-strong field.
“Honestly, my mind is blown,” Gu told the FIS website after the competition. “Coming in I didn’t have any expectations. I try not to take anything for granted. Honestly, I could not have expected two wins from these events.”
“I really just came in trying to do my best and ski the way I knew I could. Skiing my best is really the best part of this, and being rewarded for it just makes it even better.”
Born to a Chinese mother and an American father in San Francisco, US, Gu, better known as Eileen in the States, completed a naturalization process last June to represent China in international competitions.
Now she has her sights set on doing her mother’s home country proud at the 2022 Beijing Games.
A talented skier who has won many national junior titles in the US, Gu became a hit last month after winning two golds and a silver — in halfpipe, Big Air and slopestyle — at her first appearance in Winter Youth Olympics in Lausanne, Switzerland.
With Gu now on board in freeski, China’s snow sports team, which also features world-class aerial skiers and halfpipe snowboarders, is determined to challenge Western dominance on the snow in 2022.
1. How did Gu Ailing created history in her career?| A．She won two gold medals in the World Cup. |
| B．She showed her talent in skiing performance. |
| C．She displayed an impressive technical riding. |
| D．She made a massive right 900° twist twice. |
| A．Her powerful determination. | B．Her parents’ positive support. |
| C．Her deep love for competition. | D．Her relaxing and careful mind. |
| A．In China. | B．In America. |
| C．In Canada. | D．In Switzerland. |
| A．On Feb.15, 2020. | B．On Feb.14, 2020. |
| C．In January 2020. | D．In June 2019. |
Seaworld San Diego
A 6-minute tide（海潮）called Journey to Atlantis, which is to open in late May, tells the legend（传说）of the island nation. After the ride of Greek fishing boats, folks can visit a new exhibit of dolphins, which have not been on display at the park since 1998.
DETAILS: General admission is $ 46.95 for adults, $ 37.95 for children aged 3-9, free for children 2 and younger. 1-800-380-3203 or www.seaworld.com
San Diego Zoo
There’s not much in the way of new attractions. The zoo has a new panda cub（幼兽）, Mei Sheng. Nighttime Zoo, a program popular with families, starts June 26.
DETAILS: General admission is $21 for adults, $14 for children aged 3-11, free for children 2 and younger. 1 -（619）-234-5331 or www.Sandiegozoo.org
Maritime Museum of San Diego
The HMS Surprise, the 18th-century British warship featured in the film Master and commander, is on exhibit though Nov.30.
DETAILS: The ship is available for tours from 9 a.m. to 8 p.m. daily. Admission is $ 8 for adults,$ 6 for seniors and children aged 13-17, $ 5 for kids aged 6-12, and free for kids 5 and younger. 1-（619）-234-8135 or www.sdmaritime.org
Old Town Trolley Tours
Visiting relatives or friends in San Diego? They can get a hometown pass and ride or free with your paid admission.
DETAILS: The main ticket booth（售票亭）is in Old Town at 4010 Twiggs St. Hours are from 9 am to 5 pm, daily $ 25.www. historictours.com/sandiego.
1. The purpose of this text is to_______.
| A．warn | B．amuse |
| C．persuade | D．guide |
| A．Seaworld San Diego | B．San Diego Zoo |
| C．Maritime Museum of San Diego | D．Old Town Trolley Tours |
| A．$35 | B．$49 | C．$56 | D．$70 |
| A．“Love at first sight.” |
| B．“Kill two birds with one stone” |
| C．“Easy come, easy go.” |
| D．“Strike the iron while it is hot.” |
| A．San Diego Zoo will attract the largest number of children |
| B．there may be some stories about the island of Atlantis |
| C．tickets during the holidays are more expensive |
| D．the film Master and commander can be seen in Maritime Museum of San Diego |
【推荐3】As a regular Duolingo user, I enjoy the app s simple, colorful interface and short, game like exercises. The app doesn't limit how many languages you can try to learn at the same time, or how many lessons you can complete in one day, even on the free version. I use Duolingo to keep up with Spanish and German. It's an easy app because it doesn't require you to create an account right away.
For example, even if you start with little to no understanding of Spanish, the lessons are pretty gentle. You'll choose which picture- paired with the Spanish translation- accurately describes basic phrases and words. Duolingo translates from English to Spanish and back again. Most questions let you tap or click on the Spanish word to translate it in case you get stuck. The app offers additional learning resources if you click the lightbulb icon, as well as the ability to fast-track your lessons if you click the key icon.
Duolingo's “streak” feature motivates you to keep up with your language learning efforts by tracking the number of days you've reached your point goal. It can also make it feel like your world is crashing in if you lose an 80-day streak. Resources such as Duolingo Stories, which are short audio stories that allow you to check your comprehension skills as you are available online and in the apps. Duolingo also has a podcast that reiterates the lessons you've completed.
You can also subscribe to Premium for $10 per month, which gives you access to an experimental feature that lets you chat with a language tutor from a country where the language is spoken. This isn't available for all Duolingo Plus subscribers though.
1. What kind of app is Duolingo?| A．It is free of charge to users. | B．It requires users to create an account. |
| C．It enables users to learn multiple languages. | D．It provides Spanish and German versions only. |
| A．The lightbulb icon. | B．The word. |
| C．The key icon. | D．The picture. |
| A．To encourage learners to keep learning. | B．To remind you of your point goal. |
| C．To provide resources such as stories. | D．To count the number of your lost days. |
| A．To instruct. | B．To inform. | C．To entertain. | D．To comment. |
【推荐1】Hayley Arceneaux, 29 will be the youngest person to go to space when she joins Inspiralion4, a private mission led and funded by Jared Isaacman, a- billionaire businessman and pilot. The mission which is scheduled to launch in October from Cape Canaveral, Florida, will be the first mission to include non-professional astronauts. For that , the crew are receiving training in areas such as the operations of the spacecraft and the rocket that will launch it, working in microgravity, emergency preparedness and mission simulations (模拟).
Arceneaux underwent treatment for bone cancer from the age of ten in St Jude Children's Hospital in Tennessee. She endured a dozen rounds of chemotherapy (化疗) and surgery to replace her left knee and thigh bone with titanium (钛) implants after her diagnosis nearly 20 years ago. She now works at the hospital as a physician's assistant.
“Honestly, I'm not nervous at all — I am just so excited," said Arcencaux, "I think having cancer made me tough." Dr. Michael Neel, who operated on Arceneaux, said, “Hayley's story will show people that not even the sky is the limit for what you can do, whether it's in medicine, commerce or life in general."
"Right now we are at step zero. The door is closed to persons with disabilities. With this pilot project, we have the ambition to open this door and make a leap, to go from zero to one,"the European Space Agency said.
1. What can we learn about Inspiralion4?| A．Arcencaux will command the mission. |
| B．The mission will be launched privately. |
| C．The crew prepare themselves in many areas. |
| D．The mission includes no professional astronauts. |
| A．Confidence. | B．Honesty. | C．Ambition. | D．Toughness. |
| A．A leap. | B．A step. | C．A solution. | D．A chance. |
| A．Inspiration4 is to be launched in October from Cape Canaveral, Florida： |
| B．A cancer survivor is chosen as the youngest person to travel to space. |
| C．The ESA promises to employ professional astronauts with disabilities. |
| D．Jared Isaaeman funds a private spacecraft to travel in space. |
Autom is the work of Intuitive Automata, a company based in Sha Tin which claims to be a pioneer in commercial socially-interactive robots．
The robot, which stands around 38 centimeters tall, has a head that swivels (旋转), blue eyes, and a touch screen which allows the user to input information daily about exercise and diet Its creators say Autom will have a daily conversation with its user lasting up to five minutes, giving feedback and encouragement．Over time, it will interact more with the user as it gathers more information about them．
Cory Krdd, a research team manager with the Federal Emergency Management Agency claims research has shown that people find robots a more reliable source of information than on-screen-based character．
In a controlled study in Pittsburgh City Council, 15 dieters were given Autom for six weeks． Another 15 received a touch-screen computer with identical software and 15 were given a paper log．The study found, people using the robot are more likely to stick with their diets longer, in fact twice as long as those using just a paper log．
"While not one person among the computer or paper groups continued past six weeks, most who had Autom did not want to give her back at the conclusion of the study," he said．
The bottom line is that a robot creates a more powerful and long-lasting relationship with the user than a character on the screen．
Autom is expected to go on sale later this year in the United States for around $500．A robot which speaks and understands Cantonese and Mandarin in addition to English according to the demands is also being developed．
1. What's the passage mainly about?
| A．The development of Autom． |
| B．The automated way to motivation． |
| C．The working principle of robots． |
| D．The way to change the lifestyle habits． |
| A．The study was led by Cory Kidd． |
| B．The subjects were divided by two． |
| C．Every person with Autom continued past six weeks． |
| D．People using Autom gain more benefits than other people． |
| A．The price of this robot is very high． |
| B．It can communicate with people freely． |
| C．Autom can act as a coach to help lose weight． |
| D．These robots called Autom have been used widely． |
| A．Intuitive Automata． |
| B．Pittsburgh City Council． |
| C．Carnegie Mellon University． |
| D．Federal Emergency Management Agency． |
| A．The robot can help people change their lifestyle habits． |
| B．The robot can't speak English except Cantonese and Mandarin． |
| C．The robot that can speak many languages has been popular with the users． |
| D．The robot that can speak many languages meets the demand of the customers． |
【推荐3】In its early history，Chicago had floods frequently，especially in the spring，making the streets so muddy that people，horses，and carts got stuck.An old joke that was popular at the time went something like this：A man is stuck up to his waist in a muddy Chicago street.Asked if he needs help，he replies，"No，thanks.I've got a good horse under me."
The city planner decided to build an underground drainage （排水） system，but there simply wasn't enough difference between the height of the ground level and the water level.The only two options were to lower the Chicago River or raise the city.
An engineer named Ellis Chesbrough convinced the city that it had no choice but to build the pipes above ground and then cover them with dirt.This raised the level of the city's streets by as much as 12feet.
This of course created a new problem：dirt practically buried the first floors of every building in Chicago.Building owners were faced with a choice：either change the first floors of their buildings into basements，and the second stories into main floors，or hoist the entire buildings to meet the new street level.Small wood-frame buildings could be lifted fairly easily.But what about large，heavy structures like Tremont Hotel，which was a six-story brick building？
That's where George Pullman came in.He had developed some house-moving skills successfully.To lift a big structure like the Tremont Hotel，Pullman would place thousands of jackscrews （螺旋千斤顶） beneath the building's foundation.One man was assigned to operate each section of roughly 10jackscrews.At Pullman's signal each man tured his jackscrew the same amount at the same time，thereby raising the building slowly and evenly.Astonishingly，the Tremont Hotel stay open during the entire operation，and many of its guests didn't even notice anything was happening.
Some people like to say that every problem has a solution.But in Chicago's early history，every engineering solution seemed to create a new problem.Now that Chicago's waste water was draining efficiently into the Chicago River，the city's next step was to clean the polluted river.
1. The author mentions the joke to show ______ .| A．horses were fairly useful in Chicago |
| B．the Chicago people were particularly humorous |
| C．Chicago was very dangerous in the spring |
| D．Chicago's streets were extremely muddy |
| A．change | B．lift |
| C．repair | D．decorate |
| A．build the pipes above ground | B．lower the Chicago River |
| C．fight against heavy floods | D．get rid of the street dirt |
| A．popular life styles and their influences |
| B．environmental disasters and their causes |
| C．engineering problems and their solutions |
| D．successful businessmen and their achievements. |
