The concept of culture has been defined many times, and although no definition has achieved universal acceptance, most of the definitions include three central ideas: that culture is passed on from generation to generation, that a culture represents a ready-made principle for living and for making day-to-day decisions, and, finally, that the components of a culture are accepted by those in the culture as good, and true, and not to be questioned. The eminent anthropologist George Murdock has listed seventy-three items that characterize every known culture, past and present.

    The list begins with Age-grading and Athletic sports, runs to Weaning and Weather Control, and includes on the way such items as Calendar, Fire making, Property Rights, and Tool making. I would submit that even the most extreme advocate of a culture of poverty viewpoint would readily acknowledge that, with respect to almost all of these items, every American, beyond the first generation immigrant, regardless of race or class, is a member of a common culture. We all share pretty much the same sports. Maybe poor kids don't know how to play polo, and rich kids don't spend time with stickball, but we all know baseball, football, and basketball. Despite some misguided efforts to raise minor dialects to the status of separate  tongues, we all, in fact, share the same language.

    There may be differences in diction and usage, but it would be ridiculous to say that all Americans don't speak English. We have the calendar, the law, and large numbers of other cultural items in common. It may well be true that on a few of the seventy-three items there are minor variations between classes, but these kinds of things are really slight variations on a common theme.

    There are other items that show variability, not in relation to class, but in relation to religion and ethnic background — funeral customs and cooking, for example. But if there is one place in America where the melting pot is a reality, it is on the kitchen stove; in the course of one month, half the readers of this sentence have probably eaten pizza, hot pastrami, and chow mein. Specific differences that might be identified as signs of separate cultural identity are relatively insignificant within the general unity of American life; they are cultural commas and semicolons in the paragraphs and pages of American life.

    As most people know, in the last few years, sandstorms have swept across many cities and areas of North China, polluting the air and disturbing daily lives of human beings. People look dirty and suffer many kinds of illnesses, such as breath difficulty. The sandstorm is such a serious problem that it has not only weakened the industrial and agricultural development of our country but also caused a lot of trouble to the living conditions of the Chinese people.

    Therefore, effective measures should be taken as soon as possible to stop its happening. So how should we deal with the frightening sandstorms?

    Some experts offer practical advice as follows: For one thing, more money ought to be put into tree planting and forest protection in order to keep more water on the Earth. For another, government of all countries should make laws on environment protection. For example, banning the use of throw-away chopsticks and punishing illegal tree cutting. Scientists should also study and find ways to lower the grade of its destruction and to improve the environment. As for some schools, education about sandstorms should be spread properly and timely to make more and more people attach great importance to this problem.

    How people look forward to sunny days with soft wind touching their faces now and forever! The golden days can come back so long as we try our best to protect the natural environment from today on. And the fact is that what I expect is not just a dream. There are some sweet fruits from the early efforts.

    Philadelphia offers a ton of attractions that are suitable for people of every age and here are some family—friendly attractions.

    Spruce Street Harbor Park

    Spruce Street Harbor Park, one of the best urban beaches in America, is an outdoor heaven on the Delaware River waterfront. Visitors can relax in a hammock, play on the playgrounds, and play games like table tennis and giant chess. Don't miss out on the park at night, when colorful LED lights hanging from treetops make the entire area bright.

    Blue Cross River Rink

    Offering ice skating in the winter and roller skating in the summer, Blue Cross River Rink creates a fun, outdoor experience for the whole family. Visitors can play on the nine-hole mini-golf course during the summer, and enjoy eats and drinks from the on-site(现场的)bar and restaurant all year round.

    Sesame Place

    Big Bird, Elmo and the other stars of Sesame Street come out and play at Sesame Place, the only theme park in the nation starring the popular TV show's most lovable characters. A water park, interactive activities, parades, fireworks and shows add to the fun.

    Once Upon a Nation Storytelling Benches

    On summer days, uniformed and professional storytellers at 13 storytelling benches throughout Philadelphia's Historic District entertain visitors with true, free, three-to-five minute tales about the colonial(殖民的)era as part of Once Upon a Nation. Children can pick up a Story Flag at any storytelling bench, and then collect a star from every storyteller on their journeys. Flags with all the stars can get free rides on the Parx Liberty Carousel at Franklin Square.

    As for old people, some of the applications are hard to use because they didn't grow up with them. They don't have simple models of how they should work, what to do when something doesn't work or where to go for help. We make it as easy as possible to be used for people who are not familiar with the technology.

    I think there is huge potential and we are designing it. The ability to connect to friends, who remember the same movies and news and music, is really important, especially as people get old. They end up in retirement homes and they aren't always close to their friends. Allowing the network to help them connect with friends and family is a really powerful thing.

    My mother is an enthusiastic user of the Internet，although it took me years to get her to use e-mail. She was born with normal hearing, but lost it when she was 3.She was totally deaf for many years, until age 53, when she got ear aids. They work really well. That is a big change for her. But before then, her friends couldn't call her on the phone, so they insisted she use e-mail to communicate with them.

    Young people don't even think of the Internet as technology. It's just there, and they use it. There's been a very interesting change in communications styles between old people and young people. There are some kids who are now in their teens and aren't willing to make phone calls. And they think of e-mail as old-fashioned and slow.

    The reason why teens don't make phone calls seems to be that they don't know what to say. When they call they often stop for a while. They don't know what to say，and there's this silence. On the other hand, texting is considered proper, and it's okay if you don't answer. You might have been distracted. It's not considered rude. But it is considered strange if you're in this kind of voice conversation and simply stop talking.

    Honey from the African forest is not only a kind of natural sugar, it is also delicious. Most people, and many animals, like eating it. However, the only way for them to get that honey is to find a wild bees nest(巢）and take the honey from it. Often, these nests are high up in trees, and it is difficult to find them. In parts of Africa, though, people and animals looking for honey have a strange unexpected helper—a little bird called a honey guide.

    The honey guide does not actually like honey, but it does like the wax（蜂蜡） in the beehives (蜂房).

    The little bird cannot reach this wax, which is deep inside the bees' nest. So, when it finds a suitable nest, it looks for someone to help it. The honey guide gives a loud cry that attracts the attention of both passing animals and people. Once it has their attention, it flies through the forest, waiting from time to time for the curious animal or person as it leads them to the nest.

    When they finally arrive at the nest, the follower reaches in to get at the delicious honey as the bird patiently waits and watches. Some of the honey and the wax，always falls to the ground, and this is when the honey guide takes its share.

    Scientists do not know why the honey guide likes eating the wax, but it is very determined in its efforts to get it. The birds seem to be able to smell wax from a long distance away. They will quickly arrive whenever a beekeeper is taking honey from his beehives, and will even enter churches when beeswax candles are being lit.

    John Michael Thomas, 14, Florida

When John Michael Thomas decided to honor his friend and classmate Elizabeth Buckley, who died from cancer, he remembered how much she loved peacocks(孔雀).

He wanted to build a lifesized peacock fountain(喷泉) in Elizabeth's favorite park in the city. He thought it could be a place for people to relax and be inspired.

    John Michael raised $52,000 to build the fountain.

    Barrett England, 13, Utah

    The wheels began to turn for Barrett England when he heard about Karma Bike Shop, a place where young people can earn a free bike by reading and performing community(社区) service.

    Barrett visited Karma's owner with his idea: He would collect and repair used bikes and donate(捐赠) them to the shop.

    He expected to get about 10 donated bikes. In the end, Barrett received 39.

Zachary Blohm, 15, Wisconsin

    The 25­year­old playground at an elementary school near Milwaukee, Wis., was so small that only 70 of its 575 students could play on it at a time.

    That's when Zachary Blohm saved the day: He and some volunteers built a huge playground. To raise money, Zac planned T-­shirt and bake sales, sold tickets and more. He held monthly money­raising events for more than a year. Overall, he collected $130,000—enough to finish his project.

    Jack Zimmerman, 16, New Jersey

    For some people, finding a meal is as simple as opening the refrigerator. For more than 366,000 hungry kids in New Jersey, it's not that easy.

    That fact didn't sit well with Jack Zimmerman, who organized a drive to lessen childhood hunger in his state. His goal: create 40,000 packaged meals that could be donated to those in need. On game day, Jack and his volunteers started their work. After the final count, the team had packaged 47,124 meals—well above Jack's goal.