It's true to say that technology makes our lives easier. However, increasingly scientists are saying that we need to give ourselves a break—--otherwise we put ourselves at risk(风险) of developing hundreds of health problems. Over the summer the days are longer and sunnier. Why not put this free time to good use and do something away from technology?

    You could learn a new skill. There are hundreds of possibilities: cooking, a musical instrument or a new sport. Haven't you always wanted to learn how to knit(编织)? You could use your free time to practice these new things, which might lead to an exciting opportunity in the future.

    If you just want to relax, why not head to a beach? Take along your favorite book and relax on the sand, or go for a walk along the coastline. If you don't live near a beach, you could go to your local park. Why not have a picnic, or try to explore some of the local wildlife? You could even get involved in the latest craze(狂热): adult coloring books! Coloring is a surprising thing to help you relax, and it can be a nice way to escape from the stress of modern life!

    Whatever you choose to do, try something new! You might surprise yourself and find a hidden gift within you; you might make new friends along the way. Next time you find yourself changing TV channels(频道) from one to another without a clear purpose, think about what else you could spend your time doing.

    When we say older people shrink,we don't mean they become tiny enough to fit in your pocket!We just mean that it's common for older people to become a little shorter over time.This kind of shrinking can't be stopped, although people can slow this process.But why does shrinking happen at all?

    Because of gravity,cushions between the bones in the spine（脊骨）get compressed（压缩）,which makes a person lose a little height and become shorter.

    Another reason why some older people shrink is because of osteoporosis（骨质疏松）.Osteoporosis occurs when bone is broken down and not enough new bone material is made.Over time,bone is said to be lost.Bones become smaller and weaker and can easily break if someone with osteoporosis is injured.

    Older people—especially women,who generally have smaller and lighter bones to begin with—are more likely to develop osteoporosis.As years go by,a person with osteoporosis can get small breaks in bones that are called compression fractures.These breaks cause collapse of the spine and over time the person with osteoporosis can become hunched over（驼背）.

    Did you know that every day you shrink a little,too?You aren't as tall at the end of the day as you are at the beginning.That's because as the day goes on,water in the disks of the spine gets compressed due to gravity,making you just a tiny bit shorter.Don't worry,though.Once you get a good night's rest,your body recovers,and the next morning,you're standing tall again!

    Smoking and drinking alcohol can make this problem worse.Want to do something right now to build strong bones?I believe what I say will help you.

    Would you like to travel? Here is some advice for you.

    Kingsway Hall Hotel

    We offer quality service in Kingsway Hall Hotel. This location puts guests in easy reach of many places, such as the British Museum and Piccadilly Circus. Our hotel also has modern Western food, and offers a perfect dining environment. The lounge bar is a comfortable place to enjoy a drink while watching the tourists. There are hundreds of dining choices within walking distance. Non-smoking rooms are ready for guests.

    Hilton Docklands Riverside

    Located on the bank of the Thames, our hotel is about two miles east of Tower Bridge and 36 miles from London Heathrow Airport. Our hotel has a beauty salon, a flower shop and a swimming pool. The hotel also offers laundry(洗衣店)services, babysitting, shining shoes, and local area transportation.

    Windermere Hotel

    Located in the center of London, our hotel puts guests within easy reach of London's well-known buildings. Buckingham Palace and the Royal Parks are just a short walk away. Within 1.5 miles you can visit Westminster Abbey and the Houses of Parliament. The theatres, Harrods shopping centre, and the designer shops of Sloane Square and Knightsbridge are all only a short walk away or a taxi ride away.

    Air travel can be annoying. But research now suggests global warming could make it much worse. To get off the ground in really hot weather, planes may be forced to carry fewer passengers. That might mean a little more space, which would be good. However, it also would make the passengers pay more.

    Average air temperatures around the world are rising because people are polluting the air with an increasing number of greenhouse gases, which, such as carbon dioxide, are a byproduct (副产品) of burning fuels. Those warmer temperatures can influence an airplane's ability to fly because air molecules (分子) spread out more as the air warms. This produces less lift under a plane's wings, so a plane must be lighter to take off in hot weather than on cooler days.

It can even prove too dangerous for some planes to attempt a take-off. A record of June heat wave in the American Southwest, for instance, caused flight cancellations in Phoenix, Ariz. One airline's planes were cleared to operate only up to 47.8 degree Celsius. On June 20, Phoenix reached 48.3℃!

    Radley Horton is a climate scientist at Columbia University. Two years ago, he and his graduate student Ethan David Coffel studied the impact of warming at four U.S. airports and found that warming of track could triple (使成三倍) the number of days when planes face weight restrictions. Later, they explored the impact of rising temperatures on live types of commercial planes flying out of 19 of the world's busiest airports. In the coming decades, as many as one to three out of every 10 flights that take off during the hottest time of day could face weight. That would be equal to taking a dozen people off the plane, the researchers calculated.

    Thirteen-year-old Kaylee has a lot of friends—532, actually, if you count up both her Instagram followers and Facebook friends. And she spends a lot of time with them.

    But is it possible that Kaylee's online friendships could be making her lonely? That's what some experts believe Connecting online is a great way to stay in touch, they say. However, some experts worry that many kids are so busy connecting online that they might be missing out on true friendships.

    Could this be true? During your parents' childhoods, connecting with friends usually means spending time with them in the flesh. Kids played Scrabble around a table, not Words With Friends on their phones. When friends missed each other, they picked up the telephone. Friends might even write letters to each other.

    Today, most communication takes place online. A typical teen sends 2,000 texts a month and spends more than 44 hours per week in front of a screen. Much of his time is spent on social media platforms like Instagram and Facebook.

    In fact, in many ways, online communication can make friend ships stronger, “There's definitely positive influence. Kids can stay in constant contact, which means they can share more of their feelings with each other,” says Katie, co-author of the App Generation.

    Other experts, however, warn that too much online communication can get in the way of forming deep friendships. “If we are constantly checking in with our virtual worlds, we will have little time for our real world friendships.” says Rosen, a professor at California State University.

    Rosen also worries that today s kids might mistake the “friends” on the social media for true friends in life. However, in tough times, you didn't need someone to like your picture or share your tweet. You needed someone who would keep your secrets and hold your hand. You would like to talk face to face.

    US inventor Thomas Alva Edison once said: "Genius is one percent inspiration and 99 percent perspiration." He was not exaggerating. Perspiration, indeed, plays a very important role in Chinese scientist Tu Youyou's success.

    Tu was given the Nobel Prize in Physio logy or Medicine in 2015 for discovering a new drug for malaria, a deadly disease caused by the bite of some types of mosquito. She is the first Chinese citizen to win a Nobel Prize in science. "It is the pride of the whole Chinese science community, which will inspire more Chinese scientists," China Daily noted.

    Malaria is a disease that infects around 200 million people and k ills about half a million people each year, according to the Economist. Tu's discovery has saved millions of lives, especially in the developing world. According to the World Health Organization, by 2013 malaria deaths had fallen by 47 percent compared with 2000.

    But the road to this achievement was a tough one to travel. In the late 1960s, during the "cultural revolution" (1966-1976), Tu joined a government project on which she began research on a new malaria drug.

    In the beginning, Tu read a lot of old folk remedies(药方), searched texts that w ere hundreds or thousands of years old and traveled to remote places.

    Over several months, Tu and her team collected over 600 plants and created a list of almost 380 possible remedies.

    "This w as the most challenging stage of the project," Tu told The Beijing News. "It was a very labor-demanding and dull job, in particular when you faced one failure after another."

    But the hard work and the dullness failed to break the team's spirit. In the following months, she and her team tested the remedies on malaria- infected mice and they found that an extract(提取物)from the plant qinghao seemed to work w ell.

    Not that the work was easier after that. The fact that the extract didn't always work against malaria discouraged some of her teammates. But Tu was ambitious to make a contribution to the world and so she encouraged her teammates to keep going. They decided to start again from the beginning.

    In 1971, they were rewarded for their efforts. After nearly 200 failures, Tu finally made an extract that was 100 percent effective  against malaria parasites.The extract was called "Artemisin in"(青蒿素).

    Thanks to decades of hard work, Tu and her team had "provided humankind with powerful new means to combat these diseases that affect hundreds of millions of people every year," said the Nobel Prize Committee. "It has greatly improved human health and reduced suffering."