Think about the different ways that people use the wind. You can use it to fly a kite or to sail a boat. Wind is one of our cleanest and richest power sources, as well as one of the oldest. Evidence shows that windmills(风车) began to be used in ancient Iran back in the 7th century BC. They were first introduced to Europe during the 1100s, when armies returned from the Middle East with knowledge of using wind power.

    For many centuries, people used windmills to grind(磨碎) wheat into flour or pump water from deep underground. When electricity was discovered in the late 1800s, people living in remote(偏远的) areas began to use them to produce electricity. This allowed them to have electric lights and radio. However, by the 1940s when electricity was available(可利用的) to people in almost all areas of the United States, windmills were seldom used.

    During the 1970s, people started becoming concerned about the pollution that is created when coal and gas are burned to produce electricity. People also realized that the supply of coal and gas would not last forever. Then, wind was rediscovered, though it means higher costs. Today, there is a global movement to supply more and more of our electricity through the use of wind.

根据短文内容，选择最佳答案，并将选定答案的字母标号填在题前括号内。

    Do you know an outstanding junior high or high school teacher, coach, guidance counselor, librarian，or headmaster? Nominate (提名)that special teacher you'll always remember and give him/her the chance to be recognized in a famous national magazine through "Educators of the Year Contest"!

Prizes

    Cash awards will be given to those from across the country who are given the honor of Educators of the Year. Besides, your winning essays will also be published in our magazine.

Guidelines

    We will only consider essays written by teens, and nominations must be for junior high or high school educators only. Elementary school educators are not suitable.

    Convince us your educator is special. Tell us about his or her style of teaching, his or her role in school activities, and community service. What has your educator done for the entire school, your class, for you or another student? Give examples with specific details. Keep your essay between 200 and 1,000 words. Remember to include the first and last name, position, and school of your educator in your essay.

Don't forget to submit (提交)your essays through our website. You can also read our submission guidelines for more information on this website.

The Deadline

    The deadline for submitting your essays is December 30. Your essays are accepted and will appear in our magazine all over the year. Winners will be made public after the January issue is published.

    Car companies are developing vehicles that will plug into electric sockets, ust like many laptops, digital cameras, cell phones and Mp4 do. Called “plug-in vehicles”, these cars will get most of their power from electricity. Their drivers won't have to stop at gas stations as often as usual.

    The technology is more than just cool. In our car-filled world, plug-in vehicles could reduce the amount of gas we use, which keeps rising in cost now and then. Besides, driving around in these vehicles may even help the environment. Gas-burning cars produce a lot of greenhouse gas, which causes global warming.

    The first company-produced plug-in vehicles could hit the roads by 2020. But engineers still have a lot of work to do to make the technology practical and inexpensive.

    Batteries are the biggest challenge. In the plug-in-vehicle world，Li-ion(锂离子)batteries are getting the most attention. These batteries can store a large amount of energy in a small package, and they last a longer time between charges. Li-ion batteries can fit laptops, cell phones, heart instruments and other similar pocket ones.

    But because cars are so big and heavy, it would still require a suitcase-sized Li-ion batteries to power about 12km of driving. What's more, the batteries are much expensive.

    “A car filled with batteries could go a long distance,” says Ted Bohn, an electrical engineer in Chicago. “But it couldn't pull any people, and it would cost $100,000.” So researchers need to work out how to make batteries smaller and cheaper, among other questions.

    “The answers don't exist yet,” Bohn says, “As a kid, I thought someone someplace knows the answer to everything. All of these questions haven't been decided. That's what engineering is about-making a guess, running tests and getting fine results.”

    Why do some people live to be older than others? You know the standard explanations: keeping a moderate diet, engaging in regular exercise, etc. But what effect does your personality have on your longevity?Do some kinds of personalities lead to longer lives?A new study in the Journal of the American Geriatrics Society looked at this question by examining the personality characteristics of 246 children of people who had lived to be at least 100.

    The study shows that those living the longest are more outgoing,more active and less neurotic (神经质的) than other people.Long-living women are also more likely to be sympathetic and cooperative than women with a normal life span.These findings are in agreement with what you would expect from the evolutionary theory: those who like to make friends and help others can gather enough resources to make it through tough times.

    Interestingly, however, other characteristics that you might consider advantageous had no impact on whether study participants were likely to live longer.Those who were more self-disciplined,for instance,were no more likely to live to be very old.Also,being open to new ideas had no relationship to long life,which might explain all those bad-tempered old people who are fixed in their ways.

    Whether you can successfully change your personality as an adult is the subject of a longstanding psychological debate.But the new paper suggests that if you want long life,you should strive to be as outgoing as possible.

    Unfortunately, another recent study shows that your mother's personality may also help determine your longevity.That study looked at nearly 28,000 Norwegian mothers and found that those moms who were more anxious, depressed and angry were more likely to feed their kids unhealthy diets.Patterns of childhood eating can be hard to break when we're adults,which may mean that kids of depressed moms end up dying younger.

    Personality isn't destiny(命运),and everyone knows that individuals can learn to change.But both studies show that long life isn't just a matter of your physical health but of your mental health.

    Many foreign students report feeling lonely or unwelcome in Australia. Those feelings are among the reasons why Australia is taking a close look at its international education industry. But wherever international students go, making friends may not always be easy. Elisabeth Gareis of Baruch College in New York surveyed 454 international students. They were attending four-year colleges and graduate schools in the American South and Northeast.

    Students from English-speaking countries and from northern and central Europe were more likely to be happy with their friendships. But 38% of the international students said they had no close friends in the United States. And half of the students from East Asia said they were unhappy with the number of American friends they had. Thirty percent said they wished their friendships could be deeper and more meaningful.

    Professor Gareis says, “Students from East Asia have cultures that are different on many levels from the culture in the United States. There are also language problems, and maybe some social skills, such as small talk, which are possibly not as important in their native countries, where it's not as important to start friendships with small talks. Many East Asian students blamed themselves for their limited friendships with Americans, for not speaking the language well enough and for not knowing the culture well enough.

    VOA's Student Union blogger Jessica Stahl did her own survey to find out how American students and foreign students relate to each other. More than 100 students, about half of them American, answered her online questions.

Half of the international students and 60% of the Americans said they related as well or better to the other group than to their own group.

    Professor Gareis says: "International students who make friends with host nationals are, overall, more satisfied with their stay in the host country. They have better language skills, they have better academic performance and they have better attitudes toward the host country."

    Hot spots of drones (无人机) in Australia are getting sensors to automatically identify the aircraft and their pilots. Australia's Civil Aviation Safety Authority (CASA) said it would fix the equipment at the nation's airports starting next month. The monitors have been planned for some time, but come in the wake of 72 hours of drone-related disorder at the UK's Gatwick airport last week.

    In 2019, Australia will also start a scheme to register drone owners. The UK is also due to introduce a scheme in November that will require recreational drones weighing 250g (0.55lb) or more to be registered.

    Almost 140,000 air travellers were delayed last week after reports of drone sightings caused huge delays at Gatwick Airport. UK police are still searching for the criminals, although they have also raised the possibility that witness reports of the aircraft were mistaken. The incident “highlights” the need for a drone-spotting capability (能力), CASA spokesman Peter Gibson told the news agency Agence France-Presse. The supervision system would be able to spot the types of drone being flown, read their serial numbers and work out where the pilot was located, he said. Efforts to identify pilots would be aided by the introduction of the registration scheme for commercial and casual drone owners, he added. “2019 will witness severe action towards drone safety,” said Mr. Gibson. As well as airports and other sensitive locations, the drone-spotting systems will be fixed in other places known to be popular with drone owners such as the Sydney Harbour Bridge.

    Authorities in Australia have expressed worries about the number of drones being flown in controlled areas in recent months. Anyone breaking rules could face fines of up to 10,000 Australian dollars ($7,058; £5,600) as well as checks on the safety of their craft. “In 2019 it could be very expensive doing the wrong thing with your drone,” said Mr. Gibson. Events at Gatwick were discussed by ministers in a Christmas Eve phone conference. It is understood that the Cabinet Office “pushed” the Ministry of Defence and the Home Office to update their relevant regulations. They also discussed defence systems across the UK's airports.