America is a mobile society. Friendships between Americans can be close and real, yet disappear soon if situations change. Neither side feels hurt by this. Both may exchange Christmas greetings for a year or two, perhaps a few letters for a while — then no more. If the same two people meet again by chance, even years later, they pick up the friendship. This can be quite difficult for us Chinese to understand, because friendships between us flower more slowly but then may become lifelong feelings, extending (延伸) sometimes deeply into both families.

    Americans are ready to receive us foreigners at their homes, share their holidays, and their home life. They will enjoy welcoming us and be pleased if we accept their hospitality (好客) easily.

    Another difficult point for us Chinese to understand Americans is that although they include us warmly in their personal everyday lives, they don't show their politeness to us if it requires a great deal of time. This is usually the opposite of the practice in our country where we may be generous with our time. Sometimes, we, as hosts, will appear at airports even in the middle of the night to meet a friend. We may take days off to act as guides to our foreign friends. The Americans, however, express their welcome usually at homes, but truly can not manage the time to do a great deal with a visitor outside their daily routine. They will probably expect us to get ourselves from the airport to our own hotel by bus. And they expect that we will phone them from there. Once we arrive at their homes, the welcome will be full, warm and real. We will find ourselves treated hospitably.

    For the Americans, it is often considered more friendly to invite a friend to their homes than to go to restaurants, except for purely business matters. So accept their hospitality at home!

How did the ancient Chinese keep food warm in winter?

    Facilities like electric rice cookers, microwaves, and electric kettles, make it easy for people to keep food warm and enjoy a comfortable winter. So how did Chinese people in ancient times keep food warm in winter without these? In fact, ancient Chinese people used their own methods of heat preservation as early as the Shang and Zhou dynasties.

● “Wen Ding”, ancient rice cooker

    One of the major functions of an electric rice cooker is to keep food warm. The “Wen Ding”, an ancient cooking container, served the same purpose, but instead of using electric energy, the ancient cooking container, served the same purpose, but instead of using electric energy, the ancient cooking container preserved heart by burning fuels like charcoal.

    The “Wen Ding” unearthed in Nanjing in 1989 is thought to be the oldest of its kind discovered in China, dating back to the Stone Age, The craftsmanship of making the “Wen Ding” was developed in the Bronze Age. The bronze Ding from Shang and Zhou dynasties took on different shapes and structures.

● “Ran LU”, ancient small hot pot

    The “Ran LU” is a small size cooking vessel(器皿) made of bronze, which can be divided into three parts. A charcoal stove forms the main structure, with a bottom tray to hold charcoal ashes, and a movable cup at the top. Some experts have concluded that the vessel's structure suggests it may have been used as a small hot pot and that these vessels became popular in the Warring States Period(475—221 BC)

●Bronze You, ancient kettle

    The Bronze You was one of the most common wine containers during the Shang and Zhou dynasties. The Bronze You can also be used to warm wine. For example, the Bronze You with beast mask design, unearthed in Jiangxi province, has an opening where charcoals could be placed. Just as people today can't do without an electric kettle, the Bronze You allowed people to enjoy a hot drink.

●Bronze Yan, ancient steamer

    Although the “Wen Ding” was effective at keeping food warm, the ancient Chinese people later found that its burning produced pollution. As a result, the Bronze Yan was made with a two-tier structure and used to steam rice and other grains. After the Eastern Han Dynasty (AD 25-AD 220), further improvements to the Bronze Yan led to the modern-day steamer.

    There are quite a few advantages of wearing school uniforms. The idea may seem disagreeable at first, but considering all the positive effects coming from wearing uniforms you would be more likely to enjoy them.

    Teachers love school uniforms because it helps provide an orderly learning environment. Having students dressed in uniforms may teach them how to present themselves in a neat and professional manner. It gives students the opportunity to learn how to dress like young ladies and gentleman. And they can focus their attention on academics rather than style.

    Purchasing(购买) school uniforms is easy and needs less hesitation and consideration. No matter what the school's policy is, there are only specific essential(基本的) pieces to the wardrobe(服装) that are necessary, so it won't break the bank. A few wardrobe items can last a long time. Parents could also enjoy an easy morning, as it will take less time to choose a set of clothes for the school day.

    Students wearing uniforms will feel less pressure about what to wear or not to wear when their classmates are dressed similarly. Getting dressed before school becomes less of a chore(琐事) when students are limited in their choices, so there shouldn't be any trouble about choosing an outfit for the day and getting ready quickly. Some students may not like the lack of individuality(个性) with a uniform, but some school dress code policies may offer them the opportunities to show their unique styles.

    Uniforms today are also becoming trendier and can be seen in many areas of pop culture. Celebrities(名人)and fashion designers are using uniforms as inspiration for new looks which also appeal to students.

    Should Parents Teach Children How to Tweet?

    Social media is a seemingly endless source of concern for parents, with worries that it weakens their children's confidence and attention spans. But others counter that it could also be broadening their horizons.

    The latest round of worry was sparked by a study of the impact of social media use on 8-12- year-olds published by Anne Longfield, Children's Commissioner for England. The report focused on 32 children, who said they used social media to stay connected with friends and family and to have fun, by watching videos for example. But they also described pressures from constant contact, online comments that weaken their self-esteem, and the need to shape offline activities to make them shareable. "You see your friends going ice skating, partying or talking about how much revision they have done, and it can make you feel inadequate," says Bea, a junior school student from Bristol, UK. "It's just so hard to get away from."

    Children have to take risks on their journeys to adulthood, and desires to fit in and be popular existed before Mark Zuckerberg came along with Facebook. However, in previous generations these pressures came largely from people they knew, and they mostly stayed outside the home. Now the pressures could come from any one of the nearly 3 billion people online, and follow them from school to home, and can even continue through the night.

    The pressures do get on parents' nerves, among which the utmost concern is how their children can be protected from harms, given that social media is now integral to the way many young people interact. A good starting point is a basic understanding of childhood development milestones.

    Broadly, children have a high dependency on carers for security and guidance up to the age of 5, increasing independence and self-care from 6 to 11, and increasing autonomy and growing reliance on peers from 12-18 years old. Against this background, the suitability of social media for children of different ages should be considered respectively.

    According to Longfield's study, children should be taught about online safety from an early age, better before secondary school. There is growing evidence that efforts need to be extended to provide earlier guidance on less extreme but more common risks, including oversharing, low selfesteem, addiction and insomnia. The evidence suggests she is right. However, approaches that focus merely on the potential negatives are unlikely to work.

    "My school has tried to do a lot, but it often involves trying to drill into us how bad social media can be," says Bea. "People of my age really like social media, so I think a better approach would be if they said ‘Although it is good, here are some negatives'."

    The spine (脊柱) stands at the center of your health, providing your body with structure and support. It also contains a major collection of nerves that deliver electric signals from the rest of the body to your brain. So it's important to take care of it.

    Staying in a good position is one of the most important things to keep your spine healthy. A proper position means standing or sitting while keeping your spins straight, except for its natural bending. Positions play a vital part even when you're asleep. Stomach sleeping is far from a good idea. Many people prefer sleeping on their side, which is in the interests of their spine. Sleeping on your back has lots of benefits yet can cause lower back pain and put some pressure on your spine.

    Staying still for too long — even if your position is good — can be hard on your back. Especially if you work at a task most of the day, it's important to get up and stretch (伸展) periodically. Strength exercises with light weights like push-ups can also help by strengthening the muscles. However, don't overdo the exercise, as repeated movements can hurt the muscles around the spine, as trying to lift heavy weights with poor technique.

    Vitamins also affect the health of your spine. In particular, vitamin B and omega-3 fatty acids help keep nerves healthy. Another important part is vitamin D, which is required for strong bones. Vitamin D can come from some foods, but it's also absorbed from sunlight, so it may help to do some exercises outside. At last, many of the actions necessary to keep a spine healthy are similar to those used to protect your health in other ways. So protect your back, and the rest of the body will benefit.

    Have you ever wondered how your favorite NBA team received its famous name? All NBA teams have an interesting story or a history behind their names. Some of the names reflect the city's culture or history, others came from previous owners and many were selected through "Name the Team" contests.

    For teams like Los Angeles and Utah, the names were not always a reflection of the city. Even though Los Angeles has no lakes, the Laker name has been a city treasure for almost 40 years. Before going to Los Angeles, the team originated in Minneapolis, Minnesota. In 1948, team officials chose the name for its direct relationship to the state's motto, "The Land of 10,000 Lakes." The team name went unchanged after moving to Los Angeles in 1960.

    Because Utah's team originated in New Orleans, Louisiana, it was called the Jazz. In 1974, New Orleans club officials chose the name to represent the city for its reputation as the "jazz capital of the world." The name stayed with the team even after finding a new home in Salt Lake City, Utah in 1979.

The Chicago Bull's original owner, Richard Klein, named the team the Bulls. He picked the name because a fighting bull is relentless, and never quits. Klein, who founded the club in1966, believed these qualities were necessary for a championship team and hoped his Chicago athletes would live up to the team name. A belief that Bulls—winner of the six NBA championships have definitely followed.

    In 1967, the Indian Pacers selected their team name in a different way from most other teams. Their decision was based on what they wanted to accomplish in the NBA. Team officials chose the Pacers name because the organization wanted to set the "pace" in professional basketball.