In 1999, twelve percent of public elementary schools in the United States required students to wear uniforms. Just three years later, the amount was almost double that.

    A study of six big-city Ohio public schools showed students who were required to wear uniforms had improved graduation, behavior and attendance rates. Academic performance was unchanged.

    Some high schools in Texas have also joined in the movement. Yet studies find mixed results from requiring uniforms. And some schools have turned away from such policies.

    Supporters believe dressing the same creates a better learning environment and safer schools. The school district in Long Beach, California, was the first in the country to require uniforms in all elementary and middle schools. The example helped build national interest in uniforms as a way to deal with school violence and improve learning.

    Findings in Long Beach suggested that the policy resulted in fewer behavior problems and better attendance. But researcher Viktoria, who has looked at those findings, says they were based only on opinions about the effects of uniforms.

    She says other steps taken at the same time to improve schools in Long Beach and statewide could have influenced the findings. The district (the area marked by government) increased punishments for misbehavior. And California passed a law to reduce class sizes.

    In Florida, for example, researcher Sharon found that uniforms seemed to improve behavior and reduce violence. In Texas, Eloise found fewer discipline problems among students required to wear uniforms, but no effect on attendance.

    Sociologist David has studied school uniform policies since1998.He collected the reports in the book. In his own study, he found that reading and mathematics performance dropped after a school in Pennsylvania（宾夕法尼亚州）required uniforms.

    Political and community pressures may persuade schools to go to uniforms to improve learning. But David and others believe there is not enough evidence of a direct relationship. In fact, he says requiring uniforms may even increase discipline problems.

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    Technology is the application of knowledge to production. Thanks to modern technology, we have been able to increase greatly the efficiency of our work force. New machines and new methods have helped cut down time and expense while increasing overall output. This has meant more production and a higher standard of living. For most of us in America, modern technology is thought of as the reason why we can have cars and television sets. However, technology has also increased the amount of food available to us, by means of modern farming machinery and animal breeding techniques, and has made our life span longer via medical technology.

    Will mankind continue to live longer and have a higher quality of life? In large measure, the answer depends on technology and our ability to use it widely. If we keep making progress as we have over the past fifty years, the answer is definitely yes. The advancement of technology depends on research and development, and the latest surveys show that the united States is continuing to put billions of dollars annually(每年) into such efforts. So while we are running out of some limited resources, we may well find technological substitutes (代用品) for many of them through our research programs.

    Therefore, in the final analysis, the three major factors of production (land, labor and capital) are all influenced by technology. When we need new skills or techniques in medicine, people will start developing new technology to meet those needs. As equipment proves to be slow or inefficient, new machines will be invented. Technology responds to our needs in helping us improve our standard of living.

    The annual World Economic Forum took place in Davos, Switzerland, in Jan 23-26, 20What did Chinese entrepreneurs speak in the forum?Are there some quotable quotes for you ?

    ★Jack Ma, founder and executive chairman of Alibaba Group

    I think globalization cannot be stopped-no one can stop globalization, no one can stop trade. If trade stops, the world stops.Trade is the way to dissolve the war not cause  the war,” said Ma in Davos, “Google, Facebook,  Amazon and Alibaba—we are the luckiest companies of this century. But we have the responsibility to have a good heart, and do something good.

    ★Richard Liu, founder and chief executive officer of JD

    “Business is not only a way to make money but also a way to contribute yourself, to help people,” Liu said in a speech in Davos. “How can we face the fractured (分化的) world? That's the topics of the Davos this year. I think a very important thing in business is cooperation. If we can unite, work together, (if) we work very closely, I think we can bring more hope to the people and we can build more trust between the people, countries and companies and partners,” he said.

    ★Jane Sun, CEO of Ctrip

    “Tourism is a sunrise industry. Since I entered Ctrip, every year there are new comers, which, first of all, shows that tourism is booming,” Sun told Sina.com in Davos. “We invested heavily in ABC. A refers to AI, B is big data, and C is cloud computing. As we continue to expand overseas, these three will be very good weapons for us. So we think those mean opportunity,”she said.

★Hu Xiaoming, president of Aliyun

    “In 2018, people will see the development in various countries more closely connected with cloud computing. More manufacturing enterprises and financial institutions will start to use 'cloud'. And cloud computing will increase the efficiency of technology and finance,”Hu told Xinhua in Davos.

    Freelance writers Wanted

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    Recently, American President Trump announced his budget. One of the budgets would cut all money to the Institute of Museum and Library services and libraries across the United States. However, as far as I'm concerned, we need to save our libraries.

    Libraries provide books and after-school programs for children. They encourage literacy (识字）with summer programs. They help inspire a life-time love of learning and reading in children of all ages. Without them, where will kids with no Internet at home do their homework? Where will kids have a place to study or borrow books after school? Therefore, we need libraries for our kids. We need them so that kids can grow up with a place, other than school , where learning and exploration is encouraged. For adults, libraries serve as a place where they can use the Internet to apply for jobs, get job training, early voting centers as well as book clubs to help make new friends. It can also serve as a place to pick up a book and learn something new. What's more, they can also borrow a book and get away from it all.

    Libraries save our information for the next generation. When we live in an age of alternative (选择性的）facts, where science is ignored in favor of personal feelings, we need libraries now more than ever. We need them to educate ourselves on the facts and hold the government responsible for them. We need them to have strong public participation.

    If you agree with me, you shouldn't be silent on this issue. You can write or call directly to tell the president to save our libraries. You can also write to both your state Senators (参议员）and your district representative. If you do not know who they are, you can find out here. Let them know this is a beneficial issue because all people use public libraries in their daily life.

"WOW, THIS is not what I was expecting at all," says Allison, a nurse, remembering the first romance novel she ever read. Having shared the general literary bias (偏见) towards romance novels, she is now crazy about this genre (体裁). Allison was browsing in The Ripped Bodice, a romance-novel shop that recently opened in Brooklyn. The day the shop opened, the queue to get in was more than an hour long. The shop, which is uniquely-decorated, is serious in its devotion to romance novels.

The popularity of The Ripped Bodice (the second chain store devoted to romance in the district) is part of a larger shift. During the pandemic, when many were stuck at home and looking for escapist reading, fictional romance blossomed. In the year to May, romance print sales were up by 52%, according to a market-research firm. List-price sales grew by 74%. Annual growth in sales went from 6% in 2020 to more than 50% last year.

Readers have changed too. Newer fans are mostly young adults and many are teenagers. They are keen on romance novels with a central love story and a happy ending. 

"The industry has a lot of respect for what has been happening with romance," says Kristen, the manager of the market-research firm. "Now modern authors want to seek something deeper. Love is a powerful feeling. I wish that the writers could all see their way past thinking that those emotions are somehow less valuable than emotions that are built out of pain and sorrow," says Sarah, author of "Knockout"－a best-seller about romance in this season.

Librarians have noticed the shift too. Stephanie Anderson, of BookOps, which buys books for public libraries in New York and Brooklyn, notes that "the biggest challenge with romance at this point is finding the money and space to keep up with all the popular titles."