If you've ever pulled a rolling suitcase through the airport, chances are that you've also been annoyed by this common occurrence: the suitcase starts rocking back and forth on each wheel and finally tips over.
"It's a very classic phenomenon in physics," said Sylvain Courrech du Pont, a physicist at the University of Paris Diderot. "So if you disturb the system it goes very easily unstable. This is shared by many, many phenomena in nature."
Courrech du Pont and his students wanted to get to the bottom of why luggage tips. So they built what looks like the structure of a wheeled suitcase, and then filmed it rolling on a treadmill (a machine for running). Then they modeled what they saw mathematically.
And here's what they found. Under normal rolling conditions, the forward motion of the suitcase is perpendicular(垂直的) to the wheels' axis of rotation(旋转轴). All is good. But when you hit a bump or drag the handle fiercely and abruptly, one wheel lifts up. All of a sudden the pulling motion is no longer perpendicular to the still-rolling wheel's rotation axis, and the wheel corrects that by accelerating towards the center. But by that time the other wheel's coming down, the same thing happens, and now the suitcase is really rocking.
"And the first reaction you will have maybe is to slow down. But actually if you slow down you'll experience very big rocking. Therefore, the way back to a smooth ride is to keep up your speed," he says, "or move even faster, once rocking begins.
There are other solutions to suitcase instability—like doing a better packing job. "If you put heavy contents close to the axis of symmetry, then it will be stable, too."
And Courrech du Pont has one more piece of advice to avoid rocking in the first place: "If you go slow enough, it will always be stable." Keep that in mind, next time you're running to your gate.
1. What can we infer from the first two paragraphs?A.Everyone has been upset by a rolling suitcase at the airport. |
B.Physical phenomenon can be found in our daily life. |
C.The disturbance of the system results from the instability of the suitcase. |
D.The phenomenon of suitcase rolling is rare at the airport. |
A.It hits a bump |
B.One wheel lifts up. |
C.One wheel falls down. |
D.It is not perpendicular to the axis. |
A.tip it over |
B.accelerate its moving. |
C.slow down its moving |
D.drag its handle with great strength. |
A.one | B.two |
C.three | D.four |
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【推荐1】Choosing a vacation place your kids would love is quite a headache. Here are some highly preferred fun vacation places for you, which would make sure your entire family has fun together.
Hersheypark
Hersheypark, the "Chocolate Town" of USA, in Hershey, Pennsylvania, is now a main theme park with sixty rides. The amazing water rides, family rides, live concerts and shows make Hersheypark a perfect place for the young children. It also has a water park known as the "The boardwalk at Hersheypark" and a zoo.
Old Orchard Beach in Saco, Maine
The Old Orchard beach, where there is the amazing sand, water, rides, some fried food, and great fun games, can keep your kids busy and happy. Besides, there are downtown shops with great beach food.
Snowbird Resort in Snowbird, Utah
As a great place for those who enjoy the snow, Snowbird resort allows families to enjoy many activities in the winter months, such as snowboarding and ice skating. The live music concerts are held year round.
Hilton Waikoloa Village in Waikoloa, Hawaii
This is actually a fun vacation place when you are looking out for a getaway with your kids. Hilton Waikoloa Village is the place to go if you would like to have your children enter for Camp Menehune. Looking for the chance to feed birds is an exciting experience. However, an activity that your kids would enjoy most is the communication with dolphins.
1. What can visitors do in the Snowbird Resort?A.Visit a water park. | B.Enjoy ice skating with their families. |
C.See many lovely dolphins. | D.Taste great beach food. |
A.Hersheypark. | B.Old Orchard Beach. |
C.Hilton Waikoloa Village. | D.Snowbird Resort. |
A.To introduce several fun vacation places for families. |
B.To tell about the traditional relaxing holidays. |
C.To advertise the best vacation places in winter. |
D.To show some theme parks in the world. |
【推荐2】I was reading these interesting stories behind a group of great logos (标识) in the world. Personally Nike is my favorite one - it's so simple. And I liked the stories behind them, which made me forget all other things. McDonald's, Apple, Mercedes Benz and Adidas own great logos as well, and they are among my favorites.
Nike
In the Greek myth, Nike is the goddess of victory and the source of inspiration for soldiers. This logo represents the wing in the famous statue of the Greek goddess. Nike's logo was designed by Carolyn Davidson in 1971 for $ 35, and was registered as a trademark in 1995.
McDonald's
The logo was designed in 1962 by Jim Schindler to resemble the arch-shaped (拱形的) signs on the side of the company's then walk-up hamburger stand. Later on, the two golden arches were combined together to form the M. The McDonald's name was added to the logo in 1968.
Apple
There are different stories behind Apple's logo. The first logo was a reference to the religious story of Adam and Eve, in which the apple represented the fruit of the Tree of Knowledge. One year later, the second logo was designed in 1977 by Steve Jobs and Ronald Wayne, and it described Sir Isaac Newton sitting under an apple tree. This logo didn't stay long. One year later it was replaced almost immediately by graphic designer Rob Janoff's“rainbow apple", a rainbow-colored silhouette (轮廓) of an apple with a bite taken out of it. And then the rainbow-colored apple was replaced by the one-colored logo in 1998. It has not been changed so far.
Mercedes Benz
The Mercedes Benz logo, which was originally created by Gottlieb Daimler in 1909, consists of a simple description of a three-pointed star that represents its rule of the land, the sea and the air. The company was founded by Gottlieb Daimler and Wilhelm Maybach. Mercedes is the name of Maybach's elder daughter, while Benz came as a result of a combination with Benz, Cie and DMG in 1926.
Adidas
The Adidas logo, which was created by the founder of the company Adi Dassler, represents mountains, pointing towards the challenges that are seen ahead and goals that can be achieved. The logo was used for the first time in 1967.
1. What does the author think of the stories of the great logos?A.They are boring. | B.They are forgettable. |
C.They are attractive. | D.They are practical. |
A.The goddess of victory. | B.The source of inspiration for soldiers. |
C.The statue of the Greek goddess. | D.The wing of the Greek goddess. |
A.the religious story of Adam and Eve | B.a bitten apple with only one color |
C.Newton's sitting under an apple tree | D.the rainbow-colored bitten apple |
【推荐3】There are different types of money-saving apps, and all of them work in different ways. Here are 4 of the best apps that can help you save much money.
Capital One Shopping
Capital One Shopping can compare prices automatically as you shop CapifalOne online. As you add items Shopping to your cart at an online retailer, this app will search the web for better deals and coupon codes. You can follow the links to other retailers offering a better price and use the available codes to save. You can even use this app while shopping at brick-and-mortar (实体的) stores.
Paribus
There’s nothing more upsetting than buying PARIBUS something and then seeing it for sale at a lower price a few days later. Wouldn’t it be nice to get that money back? Now you can. Paribus helps you get money back by tracking your purchases from major stores and negotiating refunds. It also helps you get compensated (补偿) for late deliveries and makes sure you don’t leave it too late to return anything you bought.
Qapital
By setting goals and rules, Qapital helps you to make the most of your money and to save wisely. There’s a Payday Divvy feature that divides up your commitments between spending and saving. You’ll also be able to take part in “Money Missions”, which are fun challenges designed to give you insight into smart financial investments. If you want to invest too, you can use Qapital’s pre-built portfolios, which are tailor-made (特制的) to the timeline and amount you input.
Digit
If you can’t figure out how much you can afford to save, Digit will analyze your spending habits and allocate (分配) I a certain amount to your savings. If the app knows you have spare money to save, then it will be moved automatically, and if you don’t, it will stop, so there’s no risk of being left with no cash for the basics. You can sign up for a free trial for a month, and after that, the monthly price is $5.
1. Which of the following best describes Capital One Shopping’s function?A.Recommending brick-and-mortar stores. | B.Encouraging retailers to give coupon codes. |
C.Finding better deals for consumers. | D.Comparing the quality of different products. |
A.Capital One Shopping. | B.Paribus. | C.Digit. | D.Qapital. |
A.To compare four new apps. | B.To recommend some money-saving apps. |
C.To encourage people to save money. | D.To advertise some apps created by the author. |
【推荐1】Humans have always assumed that there is a huge gulf between animal behavior and human development. However, recent research into animals shows that animals are continuously designing innovative methods to finish their tasks. Examining the nature and results of their creativity can help us understand evolution.
Research shows that animals can also be creative. By inventing new behavioral patterns and adjusting their behavior to new contexts, as well as to changes in social and ecological environments, researchers show that animal innovation can also be diverse. For instance, chimpanzees (黑猩猩) use tools such as sharp spines and stalks to remove the hearts of palm vegetables from trees. Herring gulls (鸥) find out quite a cruel way of killing rabbits-drowning them in the sea.
Innovative species tend to survive when they enter new places, but novel behavior cannot be recognized unless “normal” behavior is studied. Researchers can now count and document the innovations that have been created by species, which would help them to quantify their creativity. Studies also show us that all animals are not equally inventive, with primates (灵长类) tending to be more innovative due to their bigger brains.
The greatest scientific significance has been the innovation shown by animals such as apes, capuchins and macaques among primates. These species of primates possess the biggest brains compared to their body sizes. They are also heavy tool users. Their broad diets and complex forms of learning are also insightful. They show an evolutionary strategy that gives them new solutions to life’s challenges.
However, even if these animals show innovativeness, they do not have the ability to im- prove upon the solutions of others. Unless they share information accurately and copy each others’ inventions, their creative inventions are likely to disappear before they can be innovated further. This ability can be managed only by humans, for we are able to build on shared knowledge.
1. What does the underlined word “gulf” in the first paragraph mean?A.Difference. | B.Conflict. | C.Balance. | D.Connection. |
A.To explain a rule. | B.To support a viewpoint. |
C.To explain a natural phenomenon. | D.To compare the two species. |
A.Their failure to share information accurately. | B.Their unwillingness to learn from each other. |
C.Their inability to take creativity forward. | D.Their ability to cooperate effectively. |
A.A biography. | B.A book review. | C.A short story. | D.A science report. |
【推荐2】Shraviya is an intelligent 8-year-old girl, who was good at her studies. She could grasp and retain anything that was explained to her just once. But over the past couple of months her grades had started dropping. Her mother often caught her staring out of the window for hours on end. Her teacher constantly pulled her up for daydreaming in class. How could she grasp what was being taught if she just was not paying attention? Finally her father took her to see a child guidance counselor.
Here her parents learnt that daydreaming is a fairly common phenomenon—and though it is not harmful, it should not be indulged in excessively. Daydreaming is easy enough to diagnose, but unfortunately it is equally difficult to get rid of. And if taken to an extreme, it can physically endanger the child or others around.
Richa Saklani, a reader from India, submitted this interesting case of Mark Twain. “There are patterns, no doubt, but creativity and genius don’t come from patterns. Mark Twain was a daydreamer—in his autobiography, he recounts an episode of when he was daydreaming when he took his infant for a drive—the clothes flew off the child and the child was blue with cold. The child died a few days later.”
Thus as you can see, while daydreaming does inspire imagination, it could also shut you out from reality. This is because the daydreamer is so lost in his thoughts that he loses his bearings entirely and is oblivious to things a- round him. If a daydreaming child happens to be on the road, this state of mind can prove to be very dangerous, or even fatal. I know of a person who almost got run over by a vehicle. He didn’t even see it coming, so lost was he in his business problems.
1. What probably caused Shraviya’s grades to drop?A.Lack of interest in study. |
B.Her sleeping in class. |
C.Daydreaming. |
D.Looking out of the window. |
A.It’s hard to find out. |
B.It’s difficult to diagnose. |
C.It’s hard to stop daydreaming. |
D.It can’t harm others. |
A.Doubtful. | B.Subjective. |
C.Appreciative. | D.Objective. |
Wikipedia was founded as a branch of Nupedia, a now-abandoned project to produce a free encyclopedia (百科全书). Nupedia required highly qualified contributors, but the writing of articles was slow. During 2000, Jimmy Wales, founder of Nupedia, and Larry Sanger, whom Wales had employed to work on the project, discussed ways of supplementing (补充) Nupedia with a more open project. Multiple sources are suggested for the idea that a wiki might allow members of the public to contribute material, and Nupedia’s first wiki went online on January 10.
There was considerable resistance on the part of Nupedia’s editors and reviewers to the idea of associating Nupedia with a Web site in the wiki format (格式), so the new project was given the name “Wikipedia” and launched on its own domain (域名), wikipedia.com, on January 15. The domain was eventually changed to the present wikipedia.org when the not-for-profit Wikimedia Foundation was launched as its new parent organization. In March 2007, the word wiki became a newly-recognized English word.
In May 2001, a wave of non-English Wikipedias was launched — in Catalan, Chinese, Dutch, Esperanto, French, German, Hebrew, Italian, Japanese, Portuguese, Russian, Spanish, and Swedish. These were soon joined by Arabic and Hungarian. In September, Polish was added. At the end of the year, Afrikaans, Norwegian, and Serbocroatian versions were announced.
Anyone with Web access can edit Wikipedia, and this openness encourages inclusion of a great amount of content. About 75,000 editors — from expert scholars to casual readers — regularly edit Wikipedia, and these experienced editors often help to create a consistent style throughout the encyclopedia.
Editors are able to watch pages and techies (科技人员) can write editing programs to keep track of or correct bad edits. Where there’re disagreements on how to present facts, editors work together to arrive at an article that fairly represents current expert opinion on the subject. Although the Wikimedia Foundation owns the site, it’s largely uninvolved in writing and daily operations.
1. Jimmy Wales wanted a more open project because ______.A.he wanted to found Wikipedia |
B.Nupedia had its own disadvantages |
C.he earned less money from Nupedia |
D.Nupedia had been abandoned |
A.gained a wide support |
B.came into being on January 15, 2000 |
C.made Nupedia better and better known to the public |
D.weren’t welcomed by all Nupedia’s editors |
A.English version. | B.Norwegian version. |
C.Hebrew version. | D.Arabic version. |
A.Any readers of the Wikipedia | B.The techies. |
C.The Wikimedia Foundation. | D.The experienced editors. |
A.Its owner contributes less to its writing. |
B.It appeals to a wider audience. |
C.Its owner was founded only recently. |
D.It was evolved from Nupedia. |
I did all this in one great day at Futuroscope. Opened in 1987, Futuroscope is one of the largest space age parks in the world. This science and technology-based theme park in France uses the most advanced technology. Its 3-D cinemas and giant movie screens provide brand new experiences of the earth and beyond. Visitors can get close to parts of the world they have never experienced, going to the bottom of the ocean, flying through the jungle or visiting the edges of the solar system. The amazing, up-to-date information together with many opportunities for hands-on learning makes the world come to life in a completely new way for visitors. Learning centers throughout the park let visitors try their own scientific experiments, as well as learn more about space travel, the undersea world and much more.
I bought tickets for myself and my friends at the park’s entrance, but tickets are also available online. Futuroscope is not only for indiviudals, but is also the perfect mix of fun and learning for class outings. Classes or other large groups that let Futuroscope know their plans in advance can get the group admission rate. For anyone coming from out of town, Futuroscope has many excellent hotels, most of which provide a shuttle service to the park. If driving, Futuroscope is within easy reach of the freeway. Plan your trip well before starting, since Futuroscope has so many shows, activities and great souvenir shops that it is difficult to see them all. Come ready to walk a lot—be sure to wear some comfortable sneakers or other walking shoes!
1. What is Futuroscope?
A.A theme park for children in America. |
B.A theme park that provides only fun and excitement. |
C.A theme park that provides people with outstanding experience without leaving the earth and the present time. |
D.A theme park that uses the most advanced technology to take people out of the earth and the present time. |
A.The things I did at Futuroscope. |
B.The history of Futuroscope. |
C.General information about how to visit the park. |
D.A general description of the park. |
A.Most of us will go to the bottom of the ocean or to the edges of the solar system. |
B.Future theme parks are places for fun and excitement but not for learning. |
C.Future theme parks allow people to see and do things without danger but with much money. |
D.In the future theme parks, there are learning centers for people to try scientific experiments. |
【推荐2】When you are reading something in English,you may often meet with a new word.What's the best way to know it?
You may look it up in the EnglishChinese dictionary.It will tell you a lot about the word:the pronunciation,the Chinese meaning and how to use the word.But how can you know where the word is in thousands of English words? How to find it in the dictionary both quickly and correctly?
First,all the English words are arranged(安排) in the letter order.In the dictionary you can first see the words beginning with letter A,then B,C,D....That means,if there are two words “desert” and “pull”,“desert” will be certainly before “pull”.Then if there are two words both beginning with the same letter,you may look at the second letter.Then the third,the fourth...For example,“pardon” is before “plough”,“judge” before “just”,etc.
Do you understand how to look up in the dictionary?The dictionary will be your good friend.I hope you'll use it as often as possible in your English study.
1. This passage is about________.A.different dictionaries |
B.new words in writing |
C.using an EnglishChinese dictionary |
D.the best way of reading |
A.how to use the word |
B.how to pronounce the word |
C.the spelling of the word |
D.who used the word first |
A.begins with A | B.begins with Z |
C.is not often used | D.is a short one |
A.century,center,business |
B.perhaps,produce,plenty |
C.straight,subject,surprise |
D.foreign,entrance,headache |
A.we have to use a dictionary when we read something in English |
B.an EnglishChinese dictionary can tell us everything about a word |
C.an EnglishChinese dictionary can help us a lot in our English study |
D.all EnglishChinese dictionary are the same |
【推荐3】My 15-year-old boy is a high achiever. He is very bright, pursuing everything he does with devotion and determination. And he is a great kid; honest, kind, faithful and caring.
Like a lot of kids who are high achievers, he is a perfectionist and very easy to fall into anxiety. That is manifested in his study, and other things he does as well. For example, he loves tennis but he is often worried about losing in the game. Now he has to stop competing because the pressure he puts on himself is becoming unhealthy. He still plays, but playing socially rather than competitively means that it’s an outlet for him rather than a source of stress.
He does not manage stress well. He puts so much pressure on himself to the point of worrying himself sick over just about every assessment. And he gets so negative about it, everything I say to him is met with negativity, every suggestion with a response that it won’t work, and honestly it’s depressing and tiring.
To help my son, I had a patient conversation with him, and he finally followed my advice about physical exercise to ease stress. Whenever he was under a lot of pressure, I would run with him for half an bour and do some push-ups to relax the pressure. Gradually, he became less nervous in the later exams and his scores became more and more stable.
Pressure from grades and perfectionism can be really hard to manage when it comes to schooling. As kids, what they need is effective communication and sincere encouragement. So I have always told and shown my son that we’re proud of him, and that pride doesn’t merely depend on top grades.
1. Which of the following best explains “manifested” underlined in paragraph 2?A.Exchanged. | B.Explored. | C.Achieved. | D.Reflected. |
A.He is a high achiever. | B.He’s easy to fall sick. |
C.He hopes to release stress. | D.He wants to win the game. |
A.His son fails to handle stress properly. | B.His son becomes tired of stress. |
C.His son is good at some sports. | D.His son is doing well at school. |
A.Taking up a new hobby. | B.Hanging out with some friends. |
C.Doing some exercise with him. | D.Talking to friends as much as possible. |
【推荐1】If you love something enough but lose it, it may just find its way back to you.
That’s a lesson a Connecticut man learned this week, when he miraculously (神奇地) recovered a dollar bill that his wife had signed years before.
Peter and Grace Bilillo were married for 50 years before Grace lost her battle with cancer. They first met in Peter’s home in Sicily when his mother introduced her unmarried son to the pretty girl down the street.
It was love at first sight. “We got married in 40 days,” said the 86-year-old man.
About seven years ago, the devoted couple each took a dollar bill and signed the names - Grace on one and Peter on the other - as a sign of their love.
“I said, ‘This dollar bill is going to be in my wallet forever,”’ Peter Bilillo said.
Forever didn’t last as long as Peter hoped, though - two years after signing the two bills, he fortuitously spent them. When his wife died, he was heartbroken.
“I felt sorry, very sorry. I thought we were never going to see those two dollars back again,” he said.
So, imagine Peter’s surprise when seven months after his beloved wife’s death, he took his granddaughter to a local subway shop, glanced at the change handed back to him by the cashier and saw his beloved Grace’s name staring at him from one of the dollar bills.
“I never thought I was going to get that dollar back again,” he said. “The first thing I said was, ‘Grace, she did this to make me happy.’”
“It’s a miracle to get it back,” he told reporters. “Who knows how many millions of people got that dollar in their hands?”
Peter says he hopes that, with a little help from Grace, the dollar with his signature will make his way back to him as well.
1. What was Peter and Grace’s first meeting like?A.They decided to marry at first sight. |
B.Grace had just won her battle with cancer. |
C.It was Peter’s mother who introduced them to each other. |
D.Peter had just had a date with a pretty girl down the street. |
A.To honor their 50th anniversary. |
B.To put something special in Peter’s wallet. |
C.To help Grace defeat her illness. |
D.To witness their love. |
A.Grace got the lost bill back to make Peter happy. |
B.There is still one signed bill that hasn’t returned. |
C.Peter took his granddaughter to look for the bill. |
D.A cashier found the last bill and gave it to Peter. |
A.accidentally. | B.intendedly. | C.expectedly. | D.intentionally. |
【推荐2】Three brown bears in the distance catches Charlie Russell’s eye. When they get a metre or so away from him, the huge animals slow down. The leading bear holds her face very close to Rusell’s. She touches his nose with her own and Russell breaks into a smile. “Hey, little bear,” he says.
Rusell, now 70, has spent more than ten springs and summers living with brown bears in the eastern-most part of Russia.“No question, bears are dangerous,” says Russell, but he also argues that fearing them prevents us from recognizing their intelligent, playful and peaceful nature. “They attack us because we abuse them.” he insists.
“What I want to do now is work on the human side of the problem,” Russell says. In Canada —a country where cities spread deep into the rural landscape and hunters kill about 450 bears annually, he is determined to change the way we treat our neighbors.
Russell was raised with the idea that “the only good bear is a dead bear.” His father, a hunter, shared stories of cruel brown bears with his five children. However, when the family’s hunting business declined in the early 1960s, Russell joined his father on an expedition to film brown bears in Alaska. Russell couldn’t help but wonder why bears behaved aggressively towards people carrying guns, but left the film-makers alone. “I suspected they didn’t like cruelty,” he says.
In 1994 he tested out his theory in British Columbia’s Khutzeymateen Inlet, where he took tourists on bear-viewing tours. One afternoon, while resting on a log between guiding trips, Russell sat still as a female brown bear casually approached. “I knew if I did not move, she would keep coming,” he later said. “I had decided to let her come as close as she wanted.” Russell spoke to the bear in gentle tones and she sat down beside him. She put her paw on his hand and Russell responded to the gesture, touching her nose, lip and teeth. These were the iron jaws featured in his father’s campfire stories, now no more threatening than the nose of a little dog. If he could repeat similar moments, Russell believed he could prove that “just by treating bears kindly, people can live safely with them”.
1. According to Russell, bears attack humans because they ________.A.mistreat them | B.are afraid of them |
C.mistake their playful tricks | D.have no idea of their real nature |
A.a good bear never dies | B.a live bear is dangerous |
C.the only good bear is dead | D.a bear is aggressive to gun holders |
A.show us how brave he is | B.warn us not to approach bears |
C.encourage us to play with bears | D.tell us to live in peace with bears |
Outlook
Outlook is back with a new series of reports to keep you up date with all that’s new in the world of entertainment.Stories go all the way from the technical to the romantic, from stage to screen.There will be reports of the stars of the moment, the stars of the future and the stars of the past.The director with his new film, the designer with the latest fashion, and the musician with the popular song are part of the new Outlook.The program is introduced by Fran Levine.
9:00 PM
Discovery
When a 10-year-old boy gets a first class degree in mathematics or an 8-year-old plays chess like a future grand master, they are considered as geniuses.Where does the quality of genius come from? Is it all in the genes or can any child be turned into a genius? And if parents do have a child who might become a genius in the future, what should they do? In this 30-minute film, Barry Johnson, the professor at School of Medicine, New York University, will help you discover the answer.
10:00 PM
Science / Health
Is it possible to beat high blood pressure without drugs? The answer is “yes”, according to the researchers at Johns Hopkins and three other medical centers.After a study of 800 persons with high blood pressure, they found that after 6 months, those devoted to weight loss-exercise and eating a low-salt, low-fat food lost about 13 pounds and became fitter.Plus, 35% of them dropped into the normal category (范畴).This week, Dr.Alan Duckworth will tell you how these people reduce their blood pressure to a level similar to what’s achieved with Hypertension drugs.
1. The main purpose of writing these three texts is ______.
A.to invite people to see films |
B.to invite people to topic discussions |
C.to attract more students to attend lectures |
D.to attract more people to watch TV programs |
A.story tellers | B.famous stars |
C.film companies | D.music fans |
A.Parents who want to send their children to a school of medicine. |
B.Children who are good at mathematics. |
C.Parents who want their child to become another Albert Einstein. |
D.Children who are interested in playing chess. |
A.Exercise plus a healthy diet. |
B.Loss of thirteen pounds in weight. |
C.Six months of exercise without drugs. |
D.Low-salt and low-fat food. |