Try this: For an entire day, forget about the clock. Eat when you're hungry and sleep when you're tired. What do you think will happen?

    You may be surprised to find that your day is much like most other days. You'll probably get hungry when you normally eat and tired when you normally sleep. Even though you don't know what time it is, your body does.

    These patterns of daily life are called circadian rhythms, and they are more than just habits. Inside our bodies are several clocklike systems that follow a roughly 24-hour cycle. Throughout the day and night, our internal clocks direct changes in temperature, body chemicals, hunger, sleepiness and more.

    Everyone's rhythms are unique, which is why you might like to stay up late while your sister always wants to go to bed early. But overall, everyone is programmed to feel tired at night and energetic during the day.

    Scientists have known for a long time that the light of day and the dark of night play important roles in setting our internal（内部的） clocks. Now, new discoveries are giving scientists insights into how these clocks work.

    Learning about our body clocks may help scientists understand why problems arise when we act out of step with our circadian rhythms. For example, traveling across time zones can make people wake up in the middle of the night. Regularly staying up late can make kids do worse on tests and quizzes. And working shifts at night leads to higher rates of heart disease, diabetes and obesity.

    “There is a growing sense that when we eat and when we sleep are important parts of how healthy we are,” says Steven Shea, Director of the Sleep Disorders Research Program at Brigham and Women's Hospital in Boston.

    Scientists still aren't sure why the timing of sleep matters so much, Shea says. But research findings suggest that our circadian rhythms are more important than we give them credit for.

    “During the night, we are prepared to sleep,” Shea says. “During the day, we are prepared to eat and move around. If you reverse (颠倒)what you are doing, everything is out of phase. That can have unfavorable consequences.”

    The number of accidents involving pedestrians (行人) wearing headphones is on the rise, a report suggests, causing fresh warning from road safety groups in Britain.

    A US-based study found a total of 116 reports of death or injury to pedestrians wearing headphones between 2004 and 2011, jumping from 16 in 2005 to 47 in 2011.

    Most victims were men (68%) and under the age of 30 (67%), with around one in ten of all cases (9%) under the age of 18.Some 89% of the cases occurred in urban areas and more than half (55%) of the victims were struck by trains .

Eighty-one of the 116 accidents (70%) resulted in the person's death—even though a warning was sounded in around a third of the cases.

    The study concluded, “The use of headphone may be a safety risk to pedestrians , especially in environments with moving vehicles（cars）. Further research is needed to determine if and how headphone use threatens pedestrian safety.” British road safety groups warned pedestrians to be careful.

    Floor Lieshout, director of Youth For Road Safety, said,“ This study shows once more the importance of using all of our senses while we are near traffic. It is important that we find an attractive way to make youth learn about the risks of wearing headphones in traffic.”

    Andrew Howard, who is the head of road safety at the Automobile Association, added that some pedestrians can be “so focused in their own little world they forget the world going on around them”. That can include headphone wearers, Howard said, but also people talking on phones.

    However, Howard said that more researches needed to be done.

    Earlier studies have shown that people wearing headphones or talking on phones can suffer “inattentional blindness” which makes them isolated (孤立) from the world around them .

    Ian Harvey, at the charity Civic Voice, said that “ to defeat isolation and to help build a civic(文明的) society, people need to interact(交往) with each other .

    He said,“ A basis for any civilized society is communication—Surfing the web, listening to MP3s, reading blogs or sending e-mail is not interacting with a person; it's interacting with a machine.

    “If people feel socially isolated, they need to have more face-to-face interactions with other human beings and in time, will begin to feel happier and more connected to the world and place they live in.”

    There are numerous amusement parks all over the world. A famous magazine, Amusement Today, does a survey among park lovers every year both in the US and overseas, based on which, “Top 5 List of the Best Amusement Parks in the World” has come out as follows:

    Disneyland, California

    Disneyland is a theme park in Anaheim, California, the US. More than 515 million guests have traveled to this American landmark from around the world since the park first opened to guests on July 17, 1955. The park consists of many world-famous sections, such as Main Street, Adventure Land, New Orleans Square, and so on.

    Magic Kingdom, Disney World, Florida

    Magic Kingdom is a theme park within the Walt Disney World Resort in Lake Buena Vista, Florida, near Orlando opened on October 1, 1971. It is the most famous theme park in Florida. The park's design and attractions don't make much difference from Disneyland Park in Anaheim.

    EPCOT, Disney World, Florida

    EPCOT is the second theme park built at the Walt Disney World Resort near Orlando, Florida. The park opened on October 1, 1982, and was named EPCOT Center from 1982 to 1993. It was the largest Disney theme park in the world until 1998, when Disney's Animal Kingdom opened.

    Disney-MGM Studios, Florida

    MGM's streets are the home for some great movie-themed attractions with a history of less than 30 years. With the addition of the Twilight Zone Tower of Terror and the Rock and

    Roller Coaster, the park is now home to Disney World's most thrilling rides.

    Universal Studios, Florida

    Go behind the scenes, beyond the screen and jump right into the action of your favorite movies at Universal Studios, the number one movie and TV theme park in the world.

    In this Pennsylvania city, Pittsburgh is shrinking but getting wealthier. Since 2000, its population has declined by 95,000 while its income per capita (人均) has shot up 24 percent. The trend is taking hold in many other cities, like Buffalo in New York, Providence in Rhode Island and New Orleans.

    Some of these areas have created more high-paying jobs in energy, health care or education. Others have managed to reshape their manufacturing (制造业) for a new economy. Higher-paying jobs have a greater effect because they create demand for additional services. “The story in Pittsburgh is very positive, and other areas are looking at it as an example of the transformation that might be possible,” said Guhan Venkatu, who wrote an economic history of the area called “Rust and Renewal” for the Federal Reserve Bank of Cleveland.

    Carnegie Mellon University and the University of Pittsburgh have helped bring tech jobs and innovation (革新) to the area by sponsoring tech centers that help graduates start companies without moving to Silicon Valley or San Francisco. This has helped keep Pittsburgh's educated young population growing even as the entire population in the city has dropped.

    Pittsburgh has more STEM (science, technology, engineering and math) jobs than other shrinking cities, about 80,000 or 7% of all jobs. STEM jobs add productivity and income growth to the area. Manufacturers of high-tech medical equipment in the Pittsburgh area also have doubled employment in the last 10 years.

    However, some experts question whether growing income per capita can really make up for a declining population. According to Patrick Adler, a researcher at the University of Toronto, population loss does matter if it means lower-skilled workers have fled because of a lack of opportunity. What's more, high-paying jobs in education and health care can disappear if the population declines too greatly. So it'd be wise to find ways to increase the population.

    Sometimes people add to what they say even when they don't talk. Gestures are the "silent language" of every culture. We point a finger or move another part of the body to show what we want to say. It is important to know the body language of every country or we may be misunderstood.

    In the USA, people greet each other with a handshake in a formal introduction. The handshake must be firm. If the handshake is weak, it is a sign of weakness or unfriendliness. Friends may place a hand on the other's arm or shoulder. Some people, usually women, greet a friend with a hug.

    Space is important to Americans. When two people talk to each other, they usually stand about two and a half feet away and at an angle (角度), so they are not facing each other directly. Americans get uncomfortable when a person stands too close. They will move back to have their space. If Americans touch another person by accident, they say, "Pardon me" or "Excuse me". Americans like to look at the other person in the eyes when they are talking. If you don't do so, it means you are bored, hiding something, or are not interested. But when you stare at someone, it is not polite.

    For Americans, thumbs-up means yes, very good, or well done. Thumbs-down means the opposite. To call a waiter, raise one hand to head level or above. To show you want the check, make a movement with your hands as if you are signing a piece of paper. It is all right to point at things but not at people with the hand and index finger (食指). Americans shake their index finger at children when they scold them and pat them on the head when they admire them.

    Learning a culture's body language is sometimes confusing. If you don't know what to do, the safest thing to do is to smile.

Cala didn't like us. Any of us. We didn't do anything to offend her and she didn't know us but that didn't matter; she still didn't like us.

As new teachers in the Emirati school, we Westerners greeted her every day. She ignored us. She came into our rooms and bypassed us as she shook hands with all the non-Westerners. Whenever we saw her, she avoided eye contact with us. Eventually, we stopped trying to befriend her.

I wouldn't say her nationality but her friends had been fired from the school. We had been employed in their places and that was enough for her to have nothing to do with us.

Well after 16 months in the school we had a secret friend gifting. To my surprise, I drew her name from the glass jar and that meant she was my secret friend. My role was to buy her a gift and say something about her when we publicly acknowledged who our secret friend was.

I decided to gift her a coloured bangle (手镯). I added a postcard and wrote "Love and Blessings, Rose Marie.

Then came the day. We all gathered in the meeting room. When you gave your gift, you said a few kind words about your secret friend and passed the gift to her. What could I say? Everyone knew she didn't like the Westerners. She taught music in the school so I said "My secret friend is someone who brings music to our ears every day." She came forward with a huge warm smile. She hugged me and kissed me on both cheeks and accepted my gift.

Since then, she smiles often. We hug and shake hands when we meet. I have seen her wear my gift several times and I am so pleased.