Social change is more likely to occur in societies where there is a mixture of different kinds of people than in societies where people are similar in many ways. The simple reason for this is that there are more different ways of looking at things present in the first kind of society. There are more ideas, more disagreements in interest, and more groups and organizations with different beliefs. In addition, there is usually a greater worldly interest and greater tolerance in mixed societies. All these factors tend to promote social change by opening more areas of life to decision. In a society where people are quite similar in many ways, there are fewer occasions for people to see the need or the opportunity for change because everything seems to be the same. And although conditions may not be satisfactory, they are at least conventional and generally agreed.

    Within a society, social change is also likely to occur more frequently and more readily in the material aspects of the culture than in the non-material, for example, in technology rather than in values; in what has been learned later in life rather than what was learned early; in the less basic and less emotional aspects of society-than in their opposites; in the simple elements rather than in the complex ones; in form rather than in substance; and in elements that are acceptable to the culture rather than in strange elements.

    Furthermore, social change is easier if it is gradual. This is one reason why change has not come more quickly to Black Americans as compared to other American minorities, because of the sharp difference in appearance between them and white people.

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    In the US, people prefer waiting for a table to sitting with people they don't know. This means a hostess may not seat a small group until a small table is available, even if a large one is. If you are sitting at a table with people you don't know, it is impolite to light up a cigarette first asking if it will disturb them.

    At American restaurants and coffee shops you are usually served tap water before you order. You may find the bread and butter is free, and if you order coffee, you may get a free refill.

    Most cities and towns have no rules about opening and closing time for stores or restaurants, though they usually do make rules for bars. Especially in large cities, stores may be open 24 hours a day.

    Serving in restaurants is often large, too large for many people. If you can't finish your meal but would like to enjoy the food later, ask your waitress or waiter for a "doggie bag". It may have a picture of a dog on it, but everybody knows you're taking the food for yourself.

    Supper and dinner are both words for the evening meal. Some people have "Sunday dinner". This is an especially big noon meal.

    Tips are not usually added to the check. They are not included in the price of the meal, either. A tip of about 15% is expected and you should leave it on the table when you leave. In some restaurants, a check is brought on a plate and you put your money there. Then the waiter or waitress brings you your change.

    I first met Paul Newman in 1968, when George Roy Hill, the director of Butch Cassidy and the Sundance Kid, introduced us in New York City. When the studio didn't want me for the film - it wanted somebody as well known as Paul - he stood up for me. I don't know how many people would have done that; they would have listened to their agents or the studio powers.

    The friendship that grew out of the experience of making that film and The Sting four years later had its root in the fact that although there was an age difference, we both came from a tradition of theater and live TV. We were respectful of craft(技艺)and focused on digging into the characters we were going to play. Both of us had the qualities and virtues that are typical of American actors: humorous, aggressive, and making fun of each other - but always with an underlying affection. Those were also at the core(核心)of our relationship off the screen.

    We shared the brief that if you're fortunate enough to have success, you should put something back - he with his Newman's Own food and his Hole in the Wall camps for kids who are seriously ill, and me with Sundance and the institute and the festival. Paul and I didn't see each other all that regularly, but sharing that brought us together. We supported each other financially and by showing up at events.

    I last saw him a few months ago. He'd been in and out of the hospital. He and I both knew what the deal was, and we didn't talk about it. Ours was a relationship that didn't need a lot of words.

    A long-term American study shows the importance of early education for poor children. The study is known as the Abecedarian(初步的) Project. It involved more than one-hundred young children from poor families in North Carolina.

    Half of the children attended an all-day program at a high-quality childcare center. The center offered educational, health and social programs. Children took part in games and activities to increase their thinking and language skills and social and emotional development. The program also included health foods for the children.

    The children attended the program from when they were a few weeks old until the age of five years. The other group of children did not attend the childcare center. After the age of five, both groups attended public school.

    Researchers compared the two groups of children. When they were babies, both groups had similar results in tests for mental and physical skills. However, from the age of eighteen months, the children in the educational child care program did much better in tests.

    The researchers tested the children again when they were twelve and fifteen years old. The tests found that the children who had been in the childcare center continued to have higher average test results. These children did much better on tests of reading and mathematics.

    A few years ago, organizers of the Abecedarian Project tested the students again. At the time, each student was twenty-one years old. They were tested for thinking and educational ability, employment, parenting and social skills. The researchers found that the young adults who had the early education still did better in reading and mathematics tests. They were more than two times as likely to go to college or to have completed college. In addition, the children who received early education were older on average, when their first child was born.

    The study offers more evidence that learning during the first months and years of life is important for all later development.

    The researchers of the Abecedarian Project believe their study shows a need for lawmakers to spend money on public early education. They believe these kinds of programs could reduce the number of children who do not complete school and are unemployed.

    Teens may become more private during adolescence (青春期) because they are learning how to be more independent, says Carl Pickhardt, a Texas­based scientist who studies parenting adolescents. "As they enter adolescence, parents have less control," he says. "You're going to have less communication with the kid who is now entering a larger and more risky world."

    However, Pickhardt says, this does not mean that parents should just sit back and do without any information. He says that parents should tell their kids that there are still things they need to know about, such as why their teen was late getting home from school one day.

    Iowa's mom Patty Link knows this fight well. The mom of three is raising two teenage boys: Graham, a 14-year-old eighth grader, and Carter, a 16-year-old high school student. She says that becoming friends with the parents of her children's friends has helped.

    "A lot of times if I want to get any information out of them, I'll say, 'Oh, I can talk to Adam's mom and she will tell me what was going on Friday night', and it will lead to some other discussion, "she says.

    Parents should watch their use of questions, Pickhardt says, because they can stand for authority (权威), and that is likely to not go over well with teens. "They want their independence to be respected, "he says. Pickhardt suggests using requests such as, "It could really help me if you could tell me," "I would really appreciate it if you let me know, "or "Could you help me better understand." But sometimes teens make mistakes and parents have to correct them. Parents should plainly (直率地) state the problem, Pickhardt says, and avoid judgments of character.

    Parents can also use technology to feel connected. One recent study showed that many teens are friends with their parents on Facebook—and only 5 percent limit what their parents can see.

    Austin Perine, a four-year-old boy, discovered that sympathy for the less fortunate can produce superhuman results.

    Once Austin's father, TJAustin, took Austin to the Firehouse Ministries, a local shelter that provides housing, food, and other services for homeless men. As they drove by the redbrick building, they saw a group of 25 homeless men standing on the street corner. "Dad, they look sad," Austin said. "Can we take them some food and make them smile?"

    That day, Austin used his allowance to buy each man a Burger King sandwich and handed the food out himself.

    Seeing what their presence meant to the men at the ministry, Austin and TJ returned the next week. After he returned every week for five weeks, word of Austin's acts of kindness spread through social media and national news outlets. Burger King jumped aboard, agreeing to donate $1,000 a month for an entire year toward the cause. Soon, churches and shelters across the country began inviting Austin to come and distribute food in other poor areas. Whereas before Austin and TJ could feed 25 to 50 people at a time, now, thanks to corporate and community support, they can feed 800 to 2,000 people at once.

    But Austin isn't just filling bellies. He's improving the lives of those he meets. On that first trip to Firehouse Ministries, TJ and Austin talked to a man named Raymont. The respect Austin gave 41-year-old Raymont touched the man. TJ helped Raymont collect all the credentials(资格) he needed to get a driver's license. The license helped Raymont get a job. And with money in the bank, he was able to rent his own apartment. All that was made possible because a little boy took the time to care.