If you are sitting, please stand up. Move your legs. Touch your toes if you can. Do anything but sit. New research shows that if you cut down on the time you spend sitting, you might live longer. Sitting less than three hours a day might extend your life by two years. Cutting television time to less than two hours a day can add one point four years to life.

    The human body is designed to move. The fact is just the opposite. Modern lifestyles and office jobs rarely give us the chance to move around. We sit while we're eating; we sit in the car; we sit while we are watching TV. And most of us sit for many hours at work. Sitting is something we do all the time. On average, Americans sit for four and a half to five hours a day. But that does not make sitting good for us.

    Though you may exercise often, that does not mean you can sit for the rest of your waking hours. We can't throw away physical activity. It is extremely important. Even if you exercise for 30 minutes a day, what goes on in the other 23 and a half hours a day is also very important.

    Changes are coming to some offices, especially in the design of desks. A “standing desk” lets people stand while they work. Another new design is called the “treadmill desk”. It is an exercise machine that lets you walk slowly in one place. Even some U.S. schools begin to experiment with desks that are part bicycle to keep children moving.

    Many companies may not buy a standing desk for everybody. However, they may get five standing desks or a treadmill desk for their employees and put them in a certain place where people can go for an hour a day to answer their emails or talk on the phone. Experts suggest some other activities: take a walk at lunchtime; walk to the offices and talk directly instead of emailing colleagues. All these activities may help you live longer.

    Phyllis Ramberg,85,lives alone in Hyattsville,Maryland,in the same house for many decades.“Children keep asking me,‘When are you going to move to one of those retirement villages?'I say,‘No,no.My friends are here, my church is close,'”Ramberg said."I've got everything I need,right in this neighborhood."A year ago,Ramberg was able to take care of her backyard.This year,she just can't do it herself."When illnesses happen,you just don't have the capability that you thought you had before,"she said.

    That's where "Aging in Place",a non-profit organization,comes in.Founder Lisa Walker says she and her friends are among the seven percent of Hyattsville residents who are 65 or older."A number of my neighbors are also around my age,"Walker said."We started talking about some of the concerns we had.Several of us had had issues with parents that were getting older and they were far away from them and didn't know how to take care of them or get support."

    Seniors can call Walker's organization with a request,for example,asking for someone to shop for groceries,do small chores around the house or drive them to the doctor.Then a volunteer is assigned to provide the help.Most of the calls are for rides to the doctor."They take me to all my medical appointments,"said Louise Battiste,who is almost 90.

    Aging in Place volunteer Sally Middlebrooks says that a review of new volunteers' background,such as driving records and any criminal history is just as important as the training they receive.“We want the seniors,people we call neighbors,to be assured that they are with safe,reliable people who are also caring people,”Middlebrooks said.

    The volunteers also gain some benefits."I've learned how to stay connected to people,your family and friends," Walker said."Do I stay close to them?Do I try to keep myself devoted to the community,relating to people younger than I am?"Middlebrooks said."I'm learning a lot about this whole process of aging,and I'm learning,to my alarm,that it's very difficult.But I'm also meeting people who amaze me with their flexibility and their sense of humor and their ability to stay very much alive despite aches and pains."

    Not all volunteers are retired.Courtney Wattai,24,is a graduate student at American University in Washington who studies care giving and plans to have a career working with seniors."That's kind of what I want to do because I want to make sure I'm able to improve their lives,"Wattai said.“I want to be involved in their lives,not just sitting at a desk doing things.I thought this would be a good way to give tribute to my grandparents and what they had done for me and my brother."

    It makes Walker happy to see the younger generation stepping up.She hopes that's how residents in her neighborhood will always care for each other.

    T-shirts out; uniforms in

    School uniforms are becoming more and more popular across the U.S.A. That's no surprise, because they offer many benefits. They immediately end the powerful social sorting and labeling (标记) that come from clothing. If all students are dressed in the same way, they will not pay too much attention to their clothing, and some of them will not be laughed at for wearing the “wrong” clothes.

    Some people are against the strict rule of school uniforms, but they do not realize that students already accept a kind of rule — wanting to look just like their friends. The difference is that the clothing students choose for themselves creates social barriers; school uniforms tear those barriers down.

    As in other places, uniforms remind the wearers of their purposes and duties. For example, when a man or woman puts on a police uniform, he or she becomes, for a time, the symbol of law and order. The uniform means to the wearer his or her special duties and sends the same message to everyone the wearer meets. People with different jobs wear uniforms of one kind or another. For students, the school uniform reminds them that their task for the six or seven hours they are in school is to get an education.

    Some parents are unhappy about uniforms, saying that school uniforms will affect their children's “creativity.” First, the clothes students choose to wear do not necessarily express the individuality. They just copy their classmates. Second, students have the rest of the day to be as creative as they like. While they're in school, their job is to master reading, writing, and math; this should take up all the creativity they have. Mastery of those skills will be good for the students to build up their creativity in every way.

    The Notre Dame fire has been put out, but its spire and a large portion of its wooden roof have been damaged. The terrible destruction causes a sudden sharp pain to people around the world. On Chinese social media network Wechat a common comment on the disaster is: "What a pity that we cannot see the damaged parts of the wonder anymore."

    But the good news is that there is at least one way of seeing them, namely via a video game called Assassin's Creed: Unity. In this game, the player can travel to one city after another and enter the buildings exactly like what they are in reality, and see Notre Dame as it was before the fire. Further, with virtual reality technology, which is already quite mature, one can even look around the undamaged Notre Dame as if it is still there. Maybe digital technology could help to better protect architectural cultural heritage.

    The idea of digitizing ancient buildings, making digital models of them so their data can be saved, dates back to the 1990s and the necessary technology has continued to advance since then. By scanning the ancient buildings with lasers, building 3D models with multiple images, as well as measuring everything precisely, engineers can make a copy as accurate as the real one.

    As computers and smartphones are hugely popular, the digital replica（复制品）has great use value  First, it allows tourists to feel the cultural relics without touching them, which helps protect them. The virtual tour of Dunhuang Grottoes in Gansu Province is a good example of this as tourists can view the paintings without standing near them. Furthermore, it can make the digitized cultural relics more famous by spreading awareness about them via the Internet. In 2000, a virtual tour of the Great Wall became very popular at the Hannover World Expo, which increased the number of foreign tourists visiting the site in the following years. Above all, it preserves all the information of the cultural relics. Even if the original ones are damaged one day, people can still know what they were like and can build a replica if desired.

    Of course, however precise a model is, it is not the original. Time is the biggest threat to a country's architectural heritage, which will always become ruins with the passing of time. Maybe we will have better technologies in the future, but the digital technology offers a practical way to preserve architectural cultural heritage at the moment.

Video calls are a common occurrence, but have you imagined being able to touch the person on the other end of the line? Scientists are making this a reality.

Researchers at the University of New South Wales, Australia, have invented a soft skin stretch device (SSD), a haptic device that can recreate the sense of touch. Haptic technology can mimic the experience of touch by stimulating localized areas of the skin in ways that are similar to what is felt in the real world, through force, vibration or motion.

Vibration is the most common haptic technology today and has been built into many electronic devices, such as one attached to the back of a trackpad in laptops. However, haptic feedback with vibration becomes less sensitive when used continuously. The existing technology also has great difficulty recreating the sense of touch with objects in virtual environments or located remotely.

The new technology overcomes issues with existing haptic devices. The research team introduced a novel method to recreate the sense of touch through soft, artificial "muscles".

It works like this: imagine you call a friend in Australia. You wear a haptic glove with the SSDs and your friend also wears a glove with 3D force sensors. If your friend picks up an object, it will physically press against your friend's fingers. And the glove with 3D force sensors will measure these interactions. The force signals can be sent to your glove so your device will generate the same 3D forces, making you experience the same sense of touch as your friend.

The haptic devices could be used in various fields, allowing users to feel objects inside a virtual world or at a distance. This could be especially beneficial during such times like the COVID-19 pandemic when people rely on video calls to stay connected with loved ones. Or it could be used in medical practices. Doctors can feel a patient's organ tissues without touching them.

It's necessary to revise(复习) after lessons so that you can really understand, remember and use what you have learned. It is also important to revise before exams. {#blank#}1{#/blank#}. 

    Find Your Place. To revise for an exam, you must first find a quiet and relaxing environment. {#blank#}2{#/blank#} It should also be a place where you will not be disturbed.

    Take Your Time. It's a good idea to make revising part of your weekly routine. The best way to do this is to revise every school day. {#blank#}3{#/blank#} Make sure that you study for no more than two hours every time, and that you take a little rest every half hour or so. This will keep you fresh and able to take in information.

    Stay Organized. {#blank#}4{#/blank#} If you are taking notes, organize them by subject, topic and date. That way when you have an exam, you can easily find the right notes to study to help you prepare.

 {#blank#}5{#/blank#} At the end of every revision, review your notes carefully to check that you have understood what you have learned. You may also consider writing out revision cards. You can then use these as summary of the subjects that you have learned.

A. Get Ready.

B. Check Your Progress.

C. It takes time to learn a new language.

D. But don't revise for too long at a time.

E. Here is some advice on how to revise well.

F. A place where you feel comfortable works best.

G. It is helpful to set up a system so you are organized.