By the mid-nineteenth century, the term “icebox” had entered the American language, but ice was still only beginning to affect the diet of ordinary citizens in the United States. The ice trade grew with the growth of cities. Ice was used in hotels, pubs, and hospitals, and by some forward-looking city dealers in fresh meat, fresh fish, and butler. After the Civil War (1861-1865), as ice was used to refrigerate freight cars(货车), it also came into household use. Even before 1880, half the ice sold in New York, Philadelphia, and Baltimore, and one-third of that sold in Boston and Chicago, went to families for their own use. This had become possible because a new household convenience, the icebox, a precursor（前身）of the modem refrigerator, had been invented.

    Making an efficient icebox was not as easy as we might now suppose. In the early nineteenth century, the knowledge of the physics of heat, which was essential to a science of refrigeration, was undeveloped. The common belief that the best icebox was one that prevented the ice from melting was of course mistaken, for it was the melting of the ice that performed the cooling. Nevertheless, early efforts to economize ice included wrapping the ice in blankets, which kept the ice from doing its job. Not until near the end of the nineteenth century did inventors achieve the delicate balance of insulation(绝缘) and circulation needed for an efficient icebox.

    But as early as 1803, an intelligent Maryland farmer, Thomas Moore, had been on the right track. He owned a farm about twenty miles outside the city of Washington, for which the village of Georgetown was the market center. When he used an icebox of his own design to transport his butter to market, he found that customers would pass up the rapidly melting butter of his competitors to pay an extra price for his butter, still fresh and hard in neat, one-pound bricks. One advantage of his icebox, Moore explained, was that fanners would no longer have to travel to market at night in order to keep their produce cool.

    A man came home from work late, tired, to find his 5-year-old son waiting for him at the door.

    “Daddy, how much money do you make each hour?”

    “If you must know, I make ＄20 each hour.”

    “Oh,” the little boy answered, with his head down. He thought for a moment, looked up and said, “Daddy, could you lend me ＄10?”

    The father was furious, “If you asked for the money to buy a toy or some other rubbish, go straight to your room and think about why you are so selfish (自私)！”

    The little boy went to his room with no words and shut the door. After a short while, the father calmed (平静) down, and started to think, “Maybe he really needs to buy something and he didn't really ask for money very often.” So he went to the little boy's room.

    “Sorry！Maybe I was too hard on your just now.” said the man, “Here's ＄10.”

    “Oh, thank you Daddy！” he said happily. Then the boy took out some coins. When the father found that the boy already had money, he got angry again.

    “Why do you want more money since you already have some?” the father shouted angrily.

    “Because I didn't have enough, but now I do.” The little boy replied, “Daddy, I have ＄20 now. Can I buy one hour of your time? Please come home early tomorrow. I would like to have dinner with you. ”

    The British are known for their sense of humor. However, it is often difficult for foreigners to understand their jokes. The main point to remember is that the British often use understatement.

     Understatement means saying less than you think or feel. For example, if someone gets very wet in a shower of rain, he might say, “It's a little damp (潮湿的) outside.” Or, if someone is very impolite and shouts at another person, someone else might say, “She isn't exactly friendly.” Understatement is often used in unpleasant situation or to make another person look silly. Understatement plays an important part in British humor.

    Another key to understanding British humor is that the British like to make fun of themselves as well as others. They often laugh about the silly and unpleasant things that happen to our everyday life when someone accidently falls over in the street. They also like to make jokes about people from different classes of society. They like to make jokes about their accents, the way they dress and the way they behave. What's more, the British love to watch comedies (喜剧) about people who do not know how to behave in society. The comedies series Mr. Bean is a good example of this kind of humor.

    Mr. Bean is the character created by British actor Rowan Atkinson in 1990. Mr. Bean doesn't talk often, and instead he uses his body movement and facial expressions to make people laugh. Perhaps what makes Mr. Bean so funny is that he does things that adults in the real world cannot do. Mr. Bean is popular in many countries around the world because you do not have to speak English to understand the humor. Because of this, many people have become familiar with the British sense of humor.

    When the telephone rings late at night, most women guess it must be one of only four or five people calling. A sister? Maybe. An emergency? Possibly. A mother? Probably not at that time of night. Much more probably it is a close female friend calling to tell you that she has split up with her boyfriend again or perhaps simply that a good movie has just started on TV.

    At a time when families are spread far and wide and marriages often end in divorce, friendships are becoming more and more important. Erika, a 32-year-old lawyer, is strengthened by her ten-year friendship with her married friend Jane. “I was very sick one night, so I called Jane at about 3:00 a.m. to talk about it,” she says. “She was very supportive and even came over to take me to the doctor's the next morning.”

    As American TV shows like Friends, which follows the lives of a very close group of young friends, have become more popular, many of us are beginning to see the value of such friendships. TV shows like this tell us that our romantic relationships may not last, but we need to keep in touch with our close friends if we want to survive.

A TV show called Real Women is about the lives and relationships of five former school friends. In this show, family, husbands, and work are all less important than friendships. One of its actresses says the show reflects her own experience. “Friendship is about commitment. I don't see some of my friends for ages but when we get together, it is as if time hasn't passed.”

    This is true of Erika and Jane's friendship. With Erika's family 200 miles away, it is Jane who keeps a spare set of keys to Erika's apartment and waters her plants whenever she is away. “Having Jane around gives me a certain amount of freedom. It is not the kind of thing that you could ask anyone to do, but she knows I would do the same for her.” Erika feels that because she no longer sees her family every day, she now enjoys a closer relationship with her best friend. Jane, who may move to a different city soon, is worried about leaving such a support system of friends. “My friends have more to do with my life than my parents and, therefore, I don't have to spend a lot of time explaining things to them. Friends are more up to date with what is happening.”

    Teen Tour Camps at SummerCamps.com

    Rock-N-Water Christian Camps

    Lotus, California, United States      Duration: 4 weeks

    Founded in 1989, Rock-N-Water is a group of highly trained Christians who want to impact young people with the joy of God's Living Word. We focus our program on biblical principles, and we use the help of nature, friendship, and challenge to develop character and have ridiculous amounts of fun.

    Odyssey Expeditions: Caribbean

    Road Town, Tortola        Duration: 3 weeks

    Odyssey Expeditions offers tropical sailing and scuba diving adventures for teenagers, with marine biology, water sports, and scuba certifications at exciting Caribbean locations. Established in 1995, Odyssey is the best opportunity to safely explore the Caribbean aboard a beautiful sailing catamaran. No experience necessary. Reserve your spot before availability. Small groups of 9-12 allow you to have the most fun!

    The G2 Academy Golf Camp

    Bluffton, South Carolina       Duration: variable

    The summer program at G2 is designed specifically for girls empowering them for their future success. Students can join weekly sessions or stay the entire summer! While participating in the G2 Academy Summer Program, students receive G2 Proprietary Training in golf, mental toughness, physical fitness, nutrition, and empowerment.

    Berklee's Aspire: Music Performance Intensive

    Boston, Massachusetts, United States         Duration: 5 weeks

    Berklee's Aspire will give you a taste of Berklee, the preeminent institute of contemporary music and the performing arts. Whether you are in middle school, high school, or beyond, there is a Berklee summer program in music, theater, and/or dance for you. You'll enjoy access to Berklee's state-of-the-art facilities as you learn from faculty who are the very best at what they do, joined by students from all over the world.

Anew study suggests that Medicare could spend billions of dollars on screening (拍片检查) smokers for lung cancer that would be better spent on helping them quit and keeping others from starting.

The new study indicated that screening more often supported smokers' beliefs that they could safely continue to smoke. Most participants remained smoking because they believed screening could catch cancer early before it would threaten their lives.

"They compared how hard it was to quit smoking with how easy it was to be screened," said Steven B. Zeliadt, the lead author of the study." They engaged in magical thinking that now there's this wonderful painless external test that can save lives."

He and seven colleagues conducted the study of 37 current smokers who were offered lung cancer screening at Department of Veteran Affairs. After being screened and told the results, they were interviewed about their smoking-related heath beliefs. For about half of those, cancer was not found." Screening lowered their motivation for quitting," the team reported in July in JAMA Internal Medicine. The participants focused only on lung cancer, ignoring other potential harm of smoking.

A national study published four years ago found that annual CT screening for lung cancer three years in a row could reduce deaths among heavy smokers by about 20 percent. In an interview, Dr. Russell P. Harris, a preventive medicine specialist at the UNC-Chapel Hill, noted that" Screening is being believed by people as an alternative to stopping smoking. But stopping smoking would have huge benefits for the individual and society." Furthermore, smoking causes many other cancers.

Dr. Harris agreed that rather than screening, money is better spent on smoking prevention. He suggested providing free stop-smoking aids, sponsoring anti-smoking advertising and raising taxes on tobacco products and the age at which people are allowed to buy them.