Whether you prefer burning the midnight oil or going to bed early so you can get up at the break of dawn depends on your genes, according to experts.

    I jump out of bed each morning, eager to start an active day. But I can hear my neighbor's alarm clock ringing non-stop every morning and I doubt he gets to work on time.

    A lot of noise comes from his flat in the evening. He's happy to stay up watching TV till after midnight, while I go to bed early and try to sleep.

    Well, it might not be his fault after all. I'm called“a lark (百灵鸟)”and my neighbor“an owl (猫头鹰)”

    We all have inside “clocks”in the brain to control all kinds of bodily functions and it is reset every day by light. These inside clocks run to a different schedule in “larks” and “owls”. If you have a fast clock, you like to do things early, and if you have a slow clock, you like to do things late.

    Because we live in a 24/7 world, scientists believe it's important to understand a person's “chronotype?—the time of the day when they function the best. It could help us lead a healthier life.

    A US professor has studied sleeping patterns and thinks work times should be changed and made more individual to fit in with our chronotypes.

    And he has advice for those who can't choose their working hours:“If that's not possible, we should be more careful about light exposure,” says the professor. “You should try to go to work not in a covered vehicle but on a bike. The minute the sun sets we should use things that have no blue light, like computer, screens and other electronic devices.”

    It's never easy to explain exactly when a specific language began, and in the case of English we can hardly regard it as a separate language before the Anglo-Saxons came to Britain. Germanic invaders (入侵者) came and settled in Britain from the north-western coastline of continental Europe in the fifth centuries. The invaders all spoke a language that was Germanic (related to Dutch, Frisian, German and the Scandinavian languages), but we'll probably never know how different their speech was from that of their continental neighbors.

    The reason that we know so little about the language in this period is because we do not have much in the way of written records from any of the Germanic languages until several centuries later. When Old English writings began to appear in the seventh and eighth centuries there was a good deal of regional variation (变化), but not more than that found in later periods.

    The Celts already lived in Britain when the Anglo-Saxons arrived, but there are few obvious signs of their language in English today. Some scholars have suggested that the Celtic tongue might have had some influence on the grammatical development of English, particularly in some parts of the country, but this is highly speculative (猜测). The number of borrowed words that have entered Old English from this language is very small. Those that survive in modern English include “comb” (a type of valley), alongside some place names.

    Tiny Countries You Never knew Existed

    Sao Tome and Principe

    Sao Tome and Principe off Africa's west coast is only 372 square miles, but it has Impressive, undamaged nature, rich in biodiverse species. The amazing needle-like volcanic peak Pico Cao Grande rises 1,000 feet into the air. The islands are home to only around 200,000 people today.

    San Marino

    Only 23 square miles with a population of just 34,000, the little-known country of San Marino, surrounded by Italy, is the world's fifth smallest country. With the UNESCO World Heritage Site of Mount Titano, the country is said to be the oldest republic in the world.

    Dominica

    Dominica covers only 290 square miles, with some of the best diving in the Caribbean, including the UNESCO World Heritage Site of volcanic Morme Trois Pitons National Park. In Dominica, you'll see rainforests, waterfalls, and coastal views. The island is also home to the only remaining population of the Kalinago, who are part of the island's 74, 900 inhabitants.

    Kiribati

    This Pacific island country 33 coral islands is 313 square-miles, but it's the only country in the world to fall into all four hemispheres (半球). The country's 109, 000 residents live in only 21 of the islands see this tropical paradise before it is no longer--rising seas are threatening to swallow the country whole.

    Four books that will change your life

    If you're already working 9-5, you might not have much time to read. With the Blinkist app, you can get the key information from the best nonfiction books in minutes, not hours or days. Start with the four most-read titles on self-improvement.

    Thirteen Things Mentally Strong People Don't Do by Amy Morin

    You can't escape misfortune in life. But you can change how you respond to it. Do you struggle to get over your failures? Or live with things out of your control? Getting over these troubles can have a great influence on your everyday life, Morin shares how her most successful therapy（治疗）patients overcame these difficulties.

    How to Stop Worrying and Start Living by Dale Carnegie

    Ever wondered why you can't stop worrying about something? No matter how hard you try, do you focus on the same issue? By defining the source of your stress, you can get over it once and for all. Camegie came up with an effective way that helps you deal with any over-thinking situation.

    Finding Your Element by Ken Rotoinson

    Society often encourages us to follow a certain linear plan. Everyone has a passion. If you don't know what yours is, it just means you haven't discovered it yet. Or perhaps you have, buth disappeared early in life. Find out how you can break free of society's strict rules and find your calling in life.

    Emotional Intelligence by Daniel Goleman

    Did you know if your pulse rate rises above 100 bpm, you're considered too emotional to think rationally（理智地）? You probably let feelings cloud your judgment more often than you know. Goleman explains how you can avoid letting your emotions rule you and make better decisions in life.

    Why do we dream? It's a question researchers have been studying for years. Now new research suggests that some dreams may result from the brain's effort to keep learning, even as we sleep.

In a study in Boston,100 volunteers were trained for an hour on a maze(迷宫). They tried to find their way through the difficult puzzle as quickly as possible. Then half of the volunteers were allowed to sleep for 90 minutes. The other half stayed awake, reading or relaxing. The ones who slept were asked to describe their dreams when they woke up.

    After the rest, the volunteers were asked again to solve the maze. Those who hadn't slept showed no improvement or did even worse after the break. Sleepers who didn't report any maze­related dreams did better but showed only a little improvement. However, four nap­takers who reported dreaming about the maze showed a surprising improvement. They scored 10 times higher after sleeping and dreaming about the maze.

    Even though the number of dreamers was small, the researchers noted that the gap in learning between the dreamers and non­dreamers was so wide that the finding was significant(有意义的).

The dreamers had all performed poorly on the test before dreaming about it. That suggests that struggling with a task might be the trigger that leads the sleeping brain to focus on it and work on how to deal with it.

    "It's almost as if your brain is going through everything that happened today," Dr Stickgold, a scientist at Harvard Medical School, said. "The things you're obsessed(迷住) with are the ones that your brain forces you to continue to do with."

    Three men traveling on a train began a conversation about the world's greatest wonders.

    "In my opinion, "the first man said, "the Egyptian pyramids are the world's greatest wonder. Although they were built thousands of years ago, they are still standing. And remember: the people who built them had only simple tools. They did not have the kind of machinery that builders and engineers have today."

    "I agree that the pyramids in Egypt are wonderful," the second man said, "but I do not think they are the greatest wonder. I believe computers are more wonderful than the pyramids. They have taken people to the moon and brought them back safely. In seconds, they carry out mathematical calculations that would take a person a hundred years to do."

    He turned to the third man and asked, "What do you think is the greatest wonder in the world?"

    The third man thought for a long time, and then he said, "Well, I agree that the pyramids are wonderful, and I agree that computers are wonderful, too. However, in my opinion, the most wonderful thing in the world is this thermos."

    And he took a thermos out of his bag and held it up.

    The other two men were very surprised. "A thermos?" they exclaimed. "But that's a simple thing."

    "Oh, no, it's not," the third man said. "In the winter you put in a hot drink and it stays hot. In the summer you put in a cold drink and it stays cold. How does the thermos know whether it's winter or summer?"