Close your eyes for a minute and imagine what life would be like if you had a hundred dollars less.Also imagine what it would be like spending the rest of your life with your eyes closed.Imagine having to read this page,not with your eyes but with your finger­tips.

     With existing medical knowledge and skills，two­thirds of the world's 42 million blind should not have to suffer.Unfortunately，rich countries possess most of this knowledge,while developing countries do not.

     ORBIS is an international non­profit organization which operates the world's only flying teaching eye hospital.ORBIS intends to help fight blindness worldwide.Inside a DC­8 aircraft，there is a fully­equipped teaching hospital with television studio and classroom.Doctors are taught the latest techniques of bringing sight back to people here.Project ORBIS also aims at promoting peaceful cooperation(合作) among countries.

     ORBIS tries to help developing countries by providing training during three­week medical programs.ORBIS has taught sight­saving techniques to over 35,000 doctors and nurses，who continue to cure tens of thousands of blind people every year.ORBIS has conducted 17 plane programs in China so far.For the seven to ten million blind in China，ORBIS is planning to do more for them.At the moment an ORBIS team is working on a long­term plan to develop a training center and to provide eye care services to Shanxi Province.ORBIS needs your help to continue their work and free people from blindness.

     For just US $38,you can help one person see;for $380 you can bring sight to 10 people;$1,300 helps teach a doctor new skills; and for $13,000 you can provide a training program for a group of doctors who can make thousands of blind people see again.Your money can open their eyes to the world.Please help ORBIS improve the quality of life for so many people less fortunate than ourselves.

    A small group of people around the world have started implanting(移植) microchips to link the body and the computer.

    Mr. Donelson and three friends, who had driven 100 miles from their homes in Loockport, New York, to have the implants put in by Dr. Jesse Villemaire, whom they had persuaded to do the work, are part of a small group, about 30 people around the world, who have independently put in microchips into their bodies, according to Web-based reports.

    At a shop William Donelson was having a four-millimeter-wide needle put into his left hand. “I'm set,”he said with a deep breath. He watched as the needle pierced(刺穿) the fleshy webbing between his thumb and a microchip was set under his skin. At last he would be able to do what he had long imagined: strengthen his body's powers through technology.

    By putting the chip inside—a radio frequency identification device (RFID)—Mr. Donelson would have at his fingertips the same magic that makes safety gates open with a knock of a card, and bridge and tunnel traffic flow smoothly with an E-Zpass. With a wave of his hand he plans to connect with his computer, open doors and unlock his car.

    Implanting the chip was relatively simple task but very meaningful to Mr. Doneselson, a 21-year-old computer networking student so interested in the link between technology and the body that he has data-input jacks(数据输入插空) inside his body. They might lead to an imagined future when people can be connected directly into computers. His new chip is enclosed in a glass container no bigger than a piece of rice and has a small memory where he has stored the words “Technology”.

    Some doctors have done the piercing in people's homes, and others have implanted chips in their offices after patients signed forms showing the fact that long-term studies have not been done on their safety. Piercers treat the implants much like any other medical operation steps, instructing people to keep the site dry, and advising them that swelling and redness should last a week.

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    What are American high schools like? Well, I'm happy to tell you what I know.

    When I started school here, it had already been a week since the school opened. At this school, freshmen usually go on a trip for about three days at the beginning of school. Unfortunately I missed that wonderful trip, which would have been the best time to get to know my classmates. I was really sad. I wished I'd known about it earlier.

    Despite the disappointment, however, I gradually adapted to my new life and school.

    There is a space in the basement of the teaching building where students chat and meet each other. As we do not always have the same classrooms and classmates, the school wants us to get to know each other there. Students usually come to school early, sit in that space and have fun. Around the space, there are many lockers for students to leave their books in, so that students do not have to carry a heavy schoolbag everywhere.

    It really surprises me that we have almost no textbooks. We only have textbooks for World History and Algebra 2 and they are big and heavy, like bricks. For other classes, we only need binders (活页夹) with paper in them. Without textbooks, students learn things freely and actively. For example, my humanities teacher just teaches us what is in her mind at the time. We never know what we will learn.

    Another difference between American schools and Chinese schools is that American schools care about students' morality more than their academic studies. For example, if you do not finish your homework, you will just be asked to do it later, but if you cheat or lie, you will get a warning or even be kicked out.

    I think that most students here are good at schoolwork as well, but compared to Chinese students, they can make learning a more joyful experience. I think we should take the good points from our two different kinds of education to perfect our approach to studying.

    For thousands of years, we have looked for ways to measure time. Early humans found that the regular movements of the sun, the earth> the moon, and the stars made good ways to measure time. The rising and setting of the sun were used to distinguish (辨别) day from night.

    But, eventually, people needed to tell time more accurately, or exactly. So, by using the sun's position in the sky, they divided the day into dawn, morning, midday and evening.

    Then it was noted that the sun cast a changing shadow as it moved across the sky. Time could be told more accurately by setting up a stick and marking the positions of the sun's shadow. It was the ancient Greeks who divided each position of this “sundial (日晷)” into hours.

    But the sun doesn't always shine. So, for the past 6,000 years, many other ways of keeping time have been tried. Slow-burning candles were divided into hours, and the hourglass was invented. When all the sand in the top of an hourglass has shifted to the bottom, an hour has passed.

    Later, the pendulum (摆钟), with its regular back-and-forth movement of weights, was used to move the hands on a clock. Pendulums are still used in grandfather clocks.

    Today, even more accurate clocks are in use, such as battery-operated quartz clocks (石英钟), digital clocks, and clocks run by electrical tuning forks and tiny atoms. These atomic clocks are the most accurate clocks ever invented. The exact time can be kept to within 1 second a century.

    Mya Le Thai is a scientist studying at the University of California, Irvine. She recently discovered a process that may result in batteries that last forever. Thai said she had been discouraged that the batteries for her wireless devices degrade. Over time, they fail to charge fully.

    Thai did not like to have keep her wireless laptop connected to an electrical outlet. She decided to do something about that problem.

    At first, she and her team thought about inventing a new battery. But as they experimented, Thai discovered something that might permit lithium-ion(锂离子) batteries to last forever. Lithium-ion batteries power most wireless devices. Over time, the batteries lose the ability to hold a charge. Most of these batteries have a life span of about 7,000 charging cycles before they die.

    One of the reasons lithium-ion batteries degrade is their use of nanowires(纳米线) to carry electricity. Nanowires are extremely thin. A human hair is thousands of times thicker, for example. Nanowires are extremely efficient carriers of electricity, which makes them useful in batteries. But Thai said their thinness also makes them weak. "Nanowires break over time," she said. "That's why they lose capacity."

    But, Thai had a theory: The nanowires might last longer if covered with a material. She and the team tested her theory. The team tried many coverings for the wires. PMMA was one of them. The nanowires were coated with PMMA and cycled through charges 200,000 times. The PMMA coated nanowires showed no evidence of damage. The results suggest that batteries could last forever, without losing charging ability.

    Thai hopes to continue her research to understand why this material works so well and to see if any other material could create better results.

"It's kind of cool," she said. "I'm really glad people are showing interest in my work and not just in the work itself, but also in technology and energy."

Four of the world's greatest national parks

 Komodo

 Location: Indonesia

 Area: 1,733km²

 Home to the world's largest lizard (蜥蜴), the Kcomodo dragon, Komodo National Park is made up of 29 islands in the centre of the Indonesian archipelago (群岛). The park's three main islands of Komodo, Rica and Pada r make ideal destinations for divers, as the surrounding coral reefs support a vast amount of oceanic diversity. With over 1,000 species of fish, 260 species of coral, and countless sea animals, this is an ideal spot to swim with sharks, whales, dolphins and more.

 Namib- Naukluft

Location: Namibia

 Area: 49,768km²

 In the world's oldest desert, the landscape moves. The golden dunes (沙丘) shift as winds blow and seasons pass. Visitors come to explore the dunes and it can be a real adventure. Jump in a 4×4 or hike across the sands on foot for a multi- day trail and you' ll soon find yourself deep in the Namibian wilderness. You' ll need a permit and doctor's letter to take on the longer hikes, but one- day hikes give anyone a chance to see more of the Namib.

 Tongariro

 Location: New Zealand

 Area:795km²

 As New Zealand's oldest national park, Tongariro National Park is home to three active volcanoes. And here's the Tongariro Alpine Crossing, a 19.4- kilometre hike that takes you across beautiful landscapes. This park also draws in skiers during the winter seasons. The biggest ski area, Whakapapa, covers 5.5km² and has 15 lifts in all.

 Teide

 Location: Tenerife, Spain

 Area: 190km²

 This park is home to Mount Teide, the highest peak in Spain. With a height of 3,718 metres, Mount Teide is also the third largest volcanic structure on the planet. Besides, Teide National Park possesses unique plants. The most unusual among the 139 recorded species is red bugloss, which has become the symbol of the park.