Little Tom down the street calls our dog "The keep dog". Zip is a sheep dog. But when Tom tries to say " Sheep", it comes out "keep". And in a way Tom is right. Zip is always bringing things home for us to keep! I'll tell you about some of them. Zip's first present was a shoe. It was made of green silk. We didn't know how Zip found the shoe. But after a moment, Mary, my big sister, told me the shoe had a strange smell. I nodded(点头) and held my nose. "What do you think it is?" "It smells like something for cleaning. I think someone tried to clean a spot (污点) off the shoe. Then he put it at the door to dry." Along came Zip. And good-bye shoe!" I said. "We should take it back." "We can't".said my sister. "Maybe little Tom is right," Mary said. "Maybe Zip is a keep dog!"

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    The kids in this village wear dirty, ragged clothes. They sleep beside cows and sheep in huts made of sticks and mud. They have no school. Yet they all can chant the English alphabet, and some can make words.

    The key to their success : 20 tablet computers(平板电脑) dropped off in their Ethiopian village in February by a U.S. group called One Laptop Per Child.

    The goal is to find out whether kids using today's new technology can teach themselves to read in places where no schools or teachers exist. The Massachusetts Institute of Technology researchers analyzing the project data say they're already amazed. “What I think has already happened is that the kids have already learned more than they would have in one year of kindergarten,” said Matt Keller, who runs the Ethiopia program.

    The fastest learner—and the first to turn on one of the tablets—is 8-year-old Kelbesa Negusse. The device's camera was disabled to save memory, yet within weeks Kelbesa had figured out its workings and made the camera work. He called himself a lion, a marker of accomplishment in Ethiopia.

    With his tablet, Kelbasa rearranged the letters HSROE into one of the many English animal names he knows. Then he spelled words on his own. “Seven months ago he didn't know any English. That's unbelievable,” said Keller.

    The project aims to get kids to a stage called “deep reading,” where they can read to learn. It won't be in Amharic, Ethiopia's first language, but in English, which is widely seen as the ticket to higher paying jobs.

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Five years ago, David Smith wore an expensive suit to work every day. "I was a clothes addict(有瘾的人)," he jokes. "I used to carry a fresh suit to work with me, so I could change if my clothes got wrinkled(有褶皱的)." Today David wears casual clothes (便装) to the office. He hardly ever wears a necktie. "I am working harder than ever." David says, "and I need to feel comfortable."

More and more companies are allowing their office workers to wear casual clothes to work. In the United States, the change from formal to casual office wear has been gradual. In the early 1990s, many companies allowed their employees to wear casual clothes on Friday. This became known as "casual Friday". "What started out as an extra one-day-a-week benefit for employees has really become an everyday thing." said business consultant Maisly Jones.

Why have so many companies started allowing their employees to wear casual clothes? "One reason is that it's easier for a company to attract new employees if it has a casual dress code." "A lot of young people don't want to dress up for work," says Owen Black, the owner of a software company, "so it's hard to hire people if you have a conservative (保守的) dress code." Another reason is that people seem happier and more productive when they are wearing comfortable clothes. In a study conducted by Levi Company, 85 percent of employers said that they believe that casual dress improves employee morale (心境, 士气). Only 4 percent of employers said that casual dress has a negative influence on productivity. Supporters of casual office wear also argue that a casual dress code helps them save money. "Suits are expensive, if you have to wear one every day," one person said. "For the same amount of money, you can buy a lot more casual clothes."

    Weighing too much can damage your health, and obesity is a growing problem for both kids and adults around the world. Sleep might be one answer to the problem. A new study has found that elementary school students who slept too little were more likely to gain pounds.

    Past studies have shown a link between sleeping less and weighing more, but scientists have had a tough time determining "which came first, the chicken or the egg," says Julie C. Lumeng of the university of Michigan in Ann Arbor. In other words, it hasn't been clear whether kids who weigh too much have trouble sleeping, or whether sleeping less leads to weight gain. Both scenarios (可能出现的情况) seemed equally possible.

    To get a better idea of which causes which, Lumeng and her colleagues interviewed the parents of 785 third graders from around the United States. The parents answered questions about how well their kids slept that year. Three years later, the parents answered the same questions. By sixth grade, 18percent of kids involved in the study were obese.

    The scientists found no relationship between weight and the students' race or gender. It also didn't matter how strict their parents were, or whether they were boys or girls. Obesity struck all of these groups equally. Instead, sleep seemed to be the key factor. Over the three years of study, the children averaged a healthy 9. 5 hours of sleep a night. Some kids, however, slept a lot more or less than others.

    For the sixth graders, every hour of sleep above the 9. 5houraverage was linked to a 20 percent lower risk of being obese. Sleep appeared doubly important for the third graders. Every extra hour of sleep they got was linked to a 40 percent drop in obesity.

    Can you remember the day when you spoke your first word? If you can, you are unusual. Try to imagine what first few months of your life were like. I am sure you just spent most of your time eating, sleeping and crying. As you grew older, you were awake more of the time. It took your parents more time to play with you and talk to you. You watched and listened curiously (好奇). You began to know that people made certain sounds to go with certain things.

    Then you began to try making the sounds you heard. And step by step you were able to make the right sound for one thing. On that day you came to understand the secret of language. The secret is that a certain sound means a certain thing. One sound might be as good as another. But it is no good as a word unless everybody agrees on its meaning. Only when a group of people use the same set of sounds of things, can they understand each other. Then, and only then do these people have a LANGUAGE.

    After you found the secret of language, you learned words. Some of the words meant things, such as BOOKS, CHAIRS and SHOES. Some words meant doing things, such as GO and SWIM, and other words describe things, such as GOOD and DIRTY. Soon you learned to put words together to express your idea, such as “I want to go out and play with my friends.” This is language. By means of language people can communicate. So we say languages are means of communication.