In the sea there are many islands. In its warm waters there are some little ones. We call them “Coral Islands”.

    A coral island is very nice to look at. It looks like a ring of land with tress, grass, and flowers on it. One part of the ring is open to the water. There is a little round lake inside the island.

    If you look into this lake, you will see beautiful coral. You may think they are flowers.

    If you look at a piece of coral, you will see many little holes in it. In each of these holes a very small sea animal has lived . These sea animals make the coral.

    They began to build under the water. Year after year, the coral grew higher and higher.

    At last it grew out of the water.

    Then the sea brought to it small trees and something else. After some years, these things changed into earth. Sometimes the wind brought seeds to this earth. Sometimes birds flew over it and brought seeds to the island.

    The little seeds grew. In a few years there were plants all over the island. In a few more years there were trees growing there.

    So you see, these islands were built little by little. The workers were very small. Do they not teach us a lesson? Can you think what the lesson is?

    This is a time of year when high school students and their families are thinking hard about college. As seniors, juniors, and parents identify their top choices, discussions typically focus on the college itself. Is the institution small or large? How strong are the academics? What is the social life like? Do I like the campus? Such considerations are important, but they can cover the all­important question: Where will these college years lead?

    Applicants should think seriously about which college on their list can best prepare them for the real world. They should look for campuses that offer well­structured programs to help them form a direction for their lives and develop the capacity to take steps along that path.

    One of the most striking recent phenomena about college graduates in America has been the "boomerang" student: the young person who goes away to college, has a great experience, graduates, and then moves back home for a year or two to figure out what to do with his or her life. This pattern has left many graduates — and their families — wondering whether it makes sense to spend four or more years at college, often at great expense, and finish with no clear sense of who they are or what they want to do next.

    The trend points to one of the great shortcomings of many of our nation's leading colleges and universities. Structured opportunities to think about life after graduation are rare. The formal curriculum focuses almost universally on the academic disciplines of the arts and sciences.  Advising on how various majors connect to pathways into the workplace is typically haphazard (没有条理的). Career planning offices are often shorthanded and marginal (不重要的) to college life.

    It doesn't need to be this way, and in recent years some of the country's top colleges have enriched their academic offerings with opportunities for students to gain real­world experiences.

    Cao Yuan, a PhD student from China, had two papers published on strange behaviour in atom-thick layers of carbon that have opened up a new field of physics.

    Pablo Jarillo-Herrero's group at MIT was already layering and rotating (旋转) sheets of carbon at different angles when Cao joined the lab in 2014. Cao's job was to find out what happened when one graphene (石墨烯) sheet was twisted only slightly wiht respect to the other, which one theory predicted would thoroughly change the material's behaviour.

    Many physicists doubted the idea. But when Cao set out to create the subtly twisted stacks, he spotted something strange. Exposed to a small electric field and cooled to 1.7 degrees above absolute zero, the graphene—which ordinarily conducts electricity—became an insulator. That by itself was surprising. But the best was yet to come: with a slight change to the field, the twisted sheets became a superconductor, in which electricity flowed without resistance.

    The ability to get atom-thick carbon into a complex electronic state through a simple rotation now has physics demanding to engineer exciting behavior in other twisted 2D materials. Some even hope that graphene could shed light on how more-complex materials superconduct at much higher temperatures. "There are so many things we can do," says Cory Dean, a physicist at Columbia University. "The opportunities at hand now are almost irresistible."

    Hitting graphene's “magic angle”—a rotation between parallel sheets of around 1.1°—involved some trial and error, but Cao was soon able to do it reliably. His experimental skill was extremely important, says his supervisor Jarillo-Herrero. Cao pioneered a method of tearing a single sheet of graphene so that he could create a stack of two layers, from which he could then fine-tune alignment (微调校准).

    Cao loves to take things apart and rebuild them. A heart, he is “a tinkerer”, his supervisor says. On his own time, this means photographing the night sky using homemade cameras and telescopes—pieces of which usually lie across Cao's office. "Every ime I go in, it's a huge mess, with computers taken apart and pieces of telescope all over his desk," says Jarillo-Herrero.

    Music is not just a set of sounds and rhythms. Its influence on the brain is much deeper than any other human experience. Keep on reading to know all those amazing powers of music.

    A recent study suggests that preterm (早产的) babies appear to experience less pain and feed more when listening to music. Experts led by Dr. Manoj Kumar of the University of Alberta, Canada, found that music had a beneficial effect on reducing pain for preterm babies experiencing painful medical tests. It also appeared to benefit full-term babies during operations.

    Many people experiencing brain damage have speech and movement-related problems. Music can help recover from brain injuries. As a different and effective treatment, doctors often advise such patients to listen to good music to improve the parts of the brain responsible for these two functions. When people with neurological (神经的) disorders hear a musical beat, it helps them to regain a balanced walk.

    Though music cannot make deafness disappear, it really can stave off the loss of hearing. There was an experiment involving 163 people where 74 were musicians. Participants were asked to pass some listening tests. Musicians heard the sounds better than non-musicians, and this difference gets clearer with age. This means that a 70-year-old musician hears better than a 50-year-old non-musician, even in a noisy environment.

    Besides, music mends a broken heart. It is not about a thrown-away love, but about a heart attack. The matter is that music can help people recover from a heart attack or heart operation by reducing blood pressure, slowing down the heartbeat rate, and reducing anxiety. Listening to the quality music produces positive emotions, improves the movement of blood, and expands blood vessels, thus, promoting quick recovery of the whole cardiovascular (心血管的) system.

Welcome to your future life!

    You get up in the morning and look into the mirror. Your face is firm and young­looking. In 2035, medical technology is better than ever. Many people at your age could live to 150, so at 40, you're not old at all. And your parents just had an anti­aging (抗衰老的) treatment. Now, all three of you look the same age!

    You say to your shirt, "Turn red." It changes from blue to red. In 2035, "smart clothes" contain particles (粒子) much smaller than the cells in your body. The particles can be programmed to change your clothes' color or pattern.

    You walk into the kitchen. You pick up the milk, but a voice says, "You shouldn't drink that!" Your fridge has read the chip (芯片) that contains information about the milk, and it knows the milk is old. In 2035, every article of food in the grocery store has such a chip.

    It's time to go to work. In 2035, cars drive themselves. Just tell your "smart car" where to go. On the way, you can call a friend using your jacket sleeve (袖子). Such "smart technology" is all around you.

    So will all these things come true? "For new technology to succeed," says scientist Andrew Zolli, "It has to be so much better that it replaces what we have already." The Internet is one example-what will be the next?

    Crossing your legs is an extremely common habit; most people don't even notice that they're doing it when they sit down. While you may find it comfortable to sit with one knee crossed over the other, it might be causing health problems that you are not aware of.

    A study published in Blood Pressure Monitoring stated that sitting with your legs crossed can increase your blood pressure. The reason for this is that the blood in your legs has to work against gravity to be pumped back to your heart and that crossing one leg over the other increases resistance(阻力), making it even harder for the blood to circulate. This causes your body to increase your blood pressure to push the blood back to the heart. You won't feel any immediate effects, but repeated, drawn­out increases in blood pressure can cause long­term health problems. So, planning to sit for a long period of time? Don't keep your legs crossed.

    Crossing your legs at the knee can also cause pressure on the major nerve in your leg that passes just below your knee and along the outside of your leg, explains Richard Graves, a medical expert. This pressure can cause numbness and temporary paralysis (麻痹) of some of the muscles in your foot and leg, preventing you from being able to raise your ankle—what we know as that "pins and needles" sensation. While the feeling of discomfort may only last a minute or two, repeatedly crossing your legs until they feel numb can cause permanent nerve damage.

    So next time you sit down, try to get yourself in the habit of sitting with both of your feet on the floor. Not only will it help your posture and stability, but it will also save your health in the long run.