You may have seen a talking parrot on a TV show, in a movie, or even in someone's home. The parrot has learned to copy sounds that people make. Birds are not the only animals that can copy the noises they hear. Dolphins, bats, and some apes also copy sounds. Now we can add elephants to this list of copycats.

    Dr. Joyce Poole is a zoologist. She studies the sounds of elephants. While she was in Kenya, she would hear strange noises made by Mlaika after sunset. Mlaika was a 10-year-old African elephant.

    Mlaika lived near a highway. Dr. Poole says, “I could not tell the difference between Mlaika's call and the distant truck noise.” She and other scientists studied Mlaika's sounds. It turned out that Mlaika was copying the sounds of the trucks driving by. Why would Mlaika copy trucks that she heard going by on the highway? Animals that are able to copy sounds may enjoy practicing new sounds. When they are kept outside of their natural environment, they may copy unusual sounds. That may be why an elephant would copy the sound of a truck.

    “Mlaika was not the only copycat elephant,” Dr. Poole says. Calimero is a 23-year-old male African elephant. He spent 18 years with two female Asian elephants. Asian elephants make chirping sounds (sounds made by birds) to talk with one another. African elephants usually do not make chirping sounds. But Calimero now does. He is copying his Asian elephant friends. Dr. Poole says that elephants need to form bonds with their family and friends. She says, “They make sounds to communicate with each other. When they are separated, they use sounds to keep in contact.”

    Parrots, dolphins, humans, and elephants show that being a copycat is one way that animals and people make new friends and keep old ones.

    Are you embarrassed to recite in class because you might give the wrong answer? Are you ashamed to share your ideas in a group？If you find yourself being shy about a lot of things, you need to understand that being shy is a very big obstacle(障碍) to one's success.{#blank#}1{#/blank#}

    First of all, you need to discover and understand the causes of your shyness.{#blank#}2{#/blank#} One of the biggest reasons why people are shy is that they were branded as a shy person. Because you heard it over and over, you believed it and thought it is true. If this is the cause, you need to stop this in your mind.{#blank#}3{#/blank#}

    One way to stop your shyness in your mind is to focus less on your weakness.{#blank#}4{#/blank#}We all have our own unique strength. So if speaking in front of many people isn't your strength, that's okay. Maybe the strength you're given is in writing. And if you think there still a lot for you to improve on your strengths and talents, that's okay too.{#blank#}5{#/blank#}

A. All you need to do is spending time training yourself to be a master in your strengths.

B. You need to dig deep and get to the roots of your shyness.

C. Then try to replace it with positive things in your life.

D. When you doubt yourself, others will doubt you.

E. The good thing is that you can overcome it.

F. Stay fearless in everything you will have to do.

G. Instead, focus more on your strength.

    Last year, Claire Noble-Randall woke up at 5:30 am every morning. She had to catch two buses to arrive in time for first-period chemistry at Ingraham High School in Seattle, US.

    Ingraham starts at 8 am, but Noble-Randall often didn't go to sleep until after midnight. “It was really hard not to fall asleep in class,” she said.

Her mom solved the problem this year when she discovered that other parents had hired a private city tour bus to take their children to the school.

    “Now, she leaves the house at a much more reasonable time 7:10 in the morning…to catch the little tour bug at 7:23 am,” said her mother, Noelle Noble.

    That may be one way to help students get more sleep. But more than 3,300 people have signed an online petition (请愿) looking for a better solution from the Seattle school district. Those who have signed the petition want all high schools and middle schools to start no earlier than 8:30 am. Most of Seattle's high schools and middle schools start at 8 am or earlier.

    Later start times for teenagers is an idea that some parents around the nation, have wanted for years. They've provided plenty of scientific evidence that teenagers tend to be night owls and delayed start times improve their health, mood, attention, and, in some cases, learning.

    But attempts to delay start times for teenagers haven't worked. Coaches don't want late dismissals (放学) cutting into sports practices; community groups don't want to wait longer for gyms and fields and before- and after-school programs don't want to change their schedules.

    This time, however, they've got Seattle School Board. President Sharon Peaslee on their side. She herself is the mother of two high school students. Peaslee hopes other board members will pass her plan calling on the district to find a way to make the changes.

    Ever wondered whether punishment actually makes people cooperate (合作)? A team of scientists created an experiment to figure it out and the results were pretty unexpected.

    To understand what they found, you have to know why these scientists were studying punishment. They were trying to figure out why people cooperate when it's often so easy to profit at others expense. Why don't friends steal from each other? Why do parents bother to feed their children? If the answer to these questions is obvious to you, congratulations, you are ahead of scientists. They're still trying to figure it out.

    In this experiment, researchers had 225 Chinese students play a game, where if the students cooperated, they'd all get a number of points. But if one defected (变节) and everyone else cooperated, the defector would get a lot of points, and the cooperators would lose out. This game represents a lot of real life situations where you struggle with a decision: work together and do OK, or run off with the rewards, ruining everybody else's day.

    This is actually a pretty ordinary economic experiment. But the researchers added two changes to see if they could mimic(糢拟)the real world better. Change one: some students played many rounds together, so they'd learn who they could trust. Change two: people could punish each other, sacrificing a point or two to destroy another player's score.

    In the end, the researchers found that playing multiple rounds made people cooperate more, which definitely mimics human society. But the whole punishment thing led to a surprise: punishing didn't actually make people cooperate more. In fact, it made them cooperate less.

    So the scientists still don't know why people cooperate, though it looks like it has more to do with groups sticking together than it does with punishment.

    Food is extremely important to us human beings and rice is one of the main food in the world. Australian researchers have discovered a way to genetically engineer rice which would provide significant health benefits to more than half the world's population.

    A study undertaken at the University of Tasmania, published in a respected journal of the National Academy of Sciences, discovered a method to increase the resistant starch (抗性淀粉）content in rice, making it more digestible and leading to lower rate of diabetes (糖尿病）and overweight.

    Steven Smith, the lead author of the study and a foreign expert for the Chinese government who has been appointed to work on crop improvement projects by the Chinese Academy of Sciences, said increasing the higher resistant starch content gave this “designer” rice many added health benefits. “We have discovered that we can increase the amount of resistant starch in cooked rice, which could provide health benefits for a large number of people in Asia and beyond,” Smith said in a media release on Friday. “The same approach can be adapted for use in other cereals, including wheat. Not only can it have benefits for diabetes and obesity, but also for disorders of the bowel(肠）including cancer.”

    Rice is the main food for more than half the world's population, providing much of the world with most of their calories. Smith said that as the rate of diabetes and obesity in Asian countries continued to grow, his “designer” rice could provide a way to limit health problems.

    “Not only does resistant starch reduce the possibility of a 'sugar hit' but it also reduces the appetite and promotes the growth of the healthy germs.” Smith said.

Smith divides his time between the University of Tasmania and his research lab in Beijing where he hopes to make significant advance in sustainable (可持续的）living.

Brushing your teeth twice a day should keep the dentist away. But if a group of scientific researchers have their wish, it will make the rest of your body healthy too. A toothbrush that checks blood sugar and bacteria while you brush is currently in development in the USA. It is one of many gadgets (小器械) proposed by engineers and doctors at the Center for Future Health in New York.

The gadgets seem fanciful, but the basic principles are simple. The gadgets should make it easy for people to detect illness long before it strikes and so seek treatment far earlier than normal. Instead of relying on hi-tech hospitals, the emphasis (重点) is shifted to the home and easy-to-use gadgets. In the long run, the technology may even prevent illness by encouraging us to lead healthier lives.

Intelligent bandages are a good example. Powerful sensors within the bandage could quickly identify tiny amounts of bacteria in a wound and determine what medicine would work best. The cut could then be treated instantly.

The biggest development is melanoma(黑色素瘤) monitor designed to give early warnings of cancer. It could be used to take a picture of your body each week, and then compare it to previous images. If a problem is found, the system would advise you to get a check-up.

If all this sounds worrying, then help is at hand. Experts are also working on a "digital doctor", complete with a comforting bedside manner. A standard computer would be able to understand your voice and answer questions about your symptoms in plain English and in a way which could calm your nerves.

Stress is no sweat either. A portable communication aid could recognize certain phrases and tones and let you know when you are about to lose your temper. The software would also suggest ways of keeping your cool.

Researchers are still struggling, however, with making the technology cheap and simple enough for the household user. That is going to be the difficult part.