We all know what a brain is. A doctor will tell you that the brain is the organ of the body in the head. It controls our body's functions, movements, emotions and thoughts. But a brain can mean so much more.

    A brain can also simply be a smart person. If a person is called brainy, he is smart and intelligent. If a family has many children but one of them is super smart, you could say, “He's the brains in the family.” And if you are the brains behind something, you are responsible for developing or organizing something. For example, Bill Gates is the brains behind Microsoft.

    Brain trust is a group of experts who give advice. Word experts say the phrase “brain trust” became popular when Franklin D. Roosevelt first ran for president in 1932. Several professors gave him advice on social and political issues（问题）facing the U.S. These professors were called his “brain trust”.

    These ways we use the word “brain” all make sense. But other ways we use the word are not so easy to understand. For example, to understand the next brain expression, you first need to know the word “drain”. As a verb, to drain means to remove something by letting it flew away. So a brain drain may sound like a disease where the brain flows out of the ears. But, brain drain is when a country's most educated people leave their countries to live in another. The brains are, sort of, draining out of the country.

    However, if people are responsible for a great idea, you could say they brainstormed it. Here, brainstorm is not an act of weather. It is a process of thinking creatively about a complex topic. For example, business leaders may use brainstorming to create new products, and government leaders may brainstorm to solve problems.

    If people are brainwashed, it does not mean their brains are nice and clean. To brainwash means to make some accept new beliefs by using repeated pressure in a forceful or tricky way. Keep in mind that brainwash is never used in a positive way.

    If English means endless new words, difficult grammar and sometimes strange pronunciation, you are wrong. Haven't you noticed that you have become smarter since you started to learn a language?

    According to a new study by a British university, learning a second language can lead to an increase in your brain power. Researchers found that learning other languages changes grey matter. This is the area of the brain which processes(处理) information. It is similar to the way that exercise builds muscles(肌肉).

    The study also found the effect is greater when the younger people learn a second language. A team led by Dr. Andrea Mechelli, from University College London, took a group of Britons who only spoke English. They were compared with a group of “early bilinguals(双语使用者) ” who had learnt a second language before the age of five, as well as a number of later learners. Scans(扫描) showed that grey matter density(密度) in the brain was greater in bilinguals who learnt a second language at an early age. But the longer a person waited before mastering a new language, the smaller the difference. “Our findings suggest that the structure of the brain is changed by the experience of learning a second language,” said the scientists.

    It means that the change itself increases the ability to learn. Professor Dylan Vaughan Jones of the University of Wales, has researched the link between bilingualism and maths skills. “Having two languages gives you two windows on the world and makes the brain more flexible(灵活的),” he said. “You are actually going beyond language and have a better understanding of different ideas.”

    The findings had the same result in a study of native Italian speakers who had learned English as a second language between the ages of two and thirty-four. Reading, wiring, and comprehension were all tested. The results showed that the younger they stared to learn, the better. “Studying a language means you get entrance to another world,” explained the scientists.

    The New Caledonia Barrier Reef (新喀里多尼亚堡礁)is located in New Caledonia in the South Pacific, and is the second-longest coral reef in the world, after Australia's Great Barrier Reef. The New Caledonia Barrier reef surrounds Grand Terre, New Caledonia's largest island, as well as the Ile des Pins and several smaller islands, reaching a length of 1, 500 km. The reef encloses(围住) in a lake of 24, 000 square kilometers, which has an average depth of 25 meters. The reefs lie up to 30 kilometers from the shore, but extend almost 200 km to the Entrecasteaux reefs in the northwest. This northwestern extension encloses the Belep Islands. Several natural passages open out to the ocean. The Boulari passage(通道), which leads to Noumea, the capital and chief port of New Caledonia, is noted for the Amedee lighthouse.

    The reef has great species diversity with a high level of endemism(动植物的特有分布), and is home to endangered dugongs, a kind of sea animal, and is an important nesting site for Green Sea Turtle.

    Most of the reefs are generally thought to be in good health. Some of the eastern reefs have been damaged by wastewater from nickel mining(镍开采)on Grand Terre. The waste from mining, agriculture, and grazing(放牧) has affected reefs near river mouths, which has been worsened by the destruction of mangrove forests, which help to keep wastes. Some reefs have been buried under several meters of wastes.

    In January 2002, the French government proposed(提议) listing New Caledonia's reefs as a UNESCO World Heritage Site. UNESCO listed New Caledonia Barrier Reef on the World Heritage List on 7 July 2008.

    Four of the World's Best Futurists(未来学家)

    Kevin Kelly

    Kevin Kelly is an author. His 1994 publication, Out of Control, discusses a future where machines and systems are so complex as to be indistinguished(难区分的) from living things.

    His latest book What Technology Wants suggests that technology is not just a mixture of wires and metals but a living thing that has its own need. The book looks out through the eyes of this global technological system to discover what it wants.

    Dr Michio Kaku

    Dr Michio Kaku is a professor of theoretical physics at the City of New York and author of The Future of the Mind and Physics of the Future.

    In The Future of the Mind , he explores the frontier of neuroscience. He predicts that one day we will be able to upload the human brain into a computer. In Physics of the Future, he predicts that glasses and contact lenses will be connected to the Internet and cars will become driverless with the power of the GPS system.

    David Brin

    Science fiction author and scientist, David Brin has received awards. In 1998, he won the Freedom of Speech Award for The Transparence Society. The book concerns threats to personal affairs and openness in the information age. In a world where the police monitor public places 24 hours a day with cameras and some credit companies can sell people's financial details to anyone willing to pay, Brin warns that surveillance(监控) technology will be used by too few people in the future. He argues that the tables should be turned and the public should have access to information like who is buying financial details from credit companies.

    Dr Ray Kurzweil

    Dr Ray Kurzweil is the main inventor of the first print-to-speech reading machine for the blind. He is the director of artificial intelligence development at Google.

    Over the past 25 years, a number of his predictions have come true. In 1990, he predicted a computer would defeat a human at chess by 1998.He predicts that by the 2020s, most diseases will go away and self-driving cars begin to take over the roads.

    A group of scientists is gathering today in the U. K. to discuss a thick piece of ice that's cracking in Antarctica, which is of the size of Delaware.

    The ice shelf is called Larsen C, and it now has a 90-mile crack running through it. The big rift (裂缝) is slicing the ice shelf from top to bottom. But this is not just another sad climate change story. It's more complicated. "A lot of things are going on deep inside the ice," says Adrian Luckman, a glaciologist.

    Luckman says climate change is certainly influencing this region. Larsen C used to have two neighbors to the north, Larsen A and Larsen B. As the air and water warmed, those ice shelves started melting and then disappeared in 1995 and 2002. But the crack in Larsen C seems to have happened on its own, for different reasons.

    Larsen C has many cracks. All ice shelves do. This particular crack has been around since at least the 1960s. The unusual part is that in 2014, this crack — and only this crack — started growing quickly. Why?

    "Well, that is a little bit of a mystery and that's why it drew itself to our attention," says Luckman. One puzzling aspect is how it managed to cut through areas of softer ice that bind (连接) the ice from neighboring glaciers into one giant sheet. Starting in 2014, that soft ice did very little to slow down this rift.

    Scientists are split on how important this crack is for the stability of the whole ice shelf. Some say if this giant section breaks off, it won't make a difference. Others disagree.

    "Ice shelves are the gates of Antarctica in a way, and the gatekeepers of Antarctica. The ice shelves are already floating, so if they fall apart it does not immediately affect sea levels. It's what they hold back -water from all the inland glaciers — that could be problematic. If all the water packed in those glaciers made their way to the sea, it could significantly raise global sea levels," says Ala Khazendar, a geophysicist.

    Whales, like all mammals(哺乳动物),need air, and come to the surface to breathe through a blowhole. A drone(无人机)that floats over the blowholes of humpback whales as they are making annual journey along Australia's east coast is being used by Australian scientists for collecting nasal mucus(鼻腔粘液)of whales.

    Vanessa Pirotta, a biologist at Macquarie University says that nasal mucus indicates the health of the whale. "It is the biological mixture that you see as a whale takes a breath as it surfaces from the water," she said. You can hear sounds of sharp breaths as a whale breathes because, after all, they are animals like you and I. So as they take a breath it is a lot of lung bacteria coming out from their lungs, which we can collect to provide a brief idea of whale health.

    Australian researchers have attached a special dish that is used in scientific tests to a drone which flies through the whale's nasal mist. As a whale comes to take a breath—you can actually see it coming to the surface on really good weather days —the drone then lowers, the dish is then opened, collecting nasal mucus for later research.

    The research could help to solve one of the secrets of another impressive creature of the deep —the Southern right whale. Its numbers have recovered on Australia's west coast since hunting became suppressed but its population on the eastern seaboard remains stubbornly low.

    In the past, studies into whale health had to rely on examining whales that were either killed or those whales that had been trapped on a beach. Drones allow scientists to collect nasal mucus from free-swimming whales to gather information in a safe way.