You don't need to get in a time-travelling machine to see how technology will change our lives, such as the way we shop. Several new technologies that are to change your buying habits already appear. Let's see what's in store for your future shopping.

    Try it on, virtually(虚拟地). Want to shop online for a new pair of glasses? You don't need to guess which pair looks best on you—use the eBay Fashion iPhone app to try a pair of glasses you're checking out on a picture of your face. But what about buying something bigger? Thanks to Microsoft Kinect's action tracking(跟踪)camera, you can cover clothes on your screen body. You can even choose the background of your virtual fitting room to improve your shopping experience.

    Get a perfect, custom fit. Everyone's body is shaped differently. To get a perfect fit, you sometimes have to get your clothes changed. But by using 3D scanning technology, all the clothes you buy will fit your body perfectly. Some companies scan(扫描)your body using High-tech to get the real sizes, so they can make special clothes just for you.

    High-tech shopping carts(推车)and checkout counters(收银台). High-tech shopping carts could be common in malls and supermarkets in the future. Microsoft Kinect-enabled carts are under test. The cart can follow you along the aisles(通道), controlled only by your movement and your voice.

    In the United States, several supermarkets use a certain set called "Scan It" that gives buyers the freedom to scan products on their own while they shop. If we don't want to wait in line before the checkout counters, we can use Toshiba's new object Recognition Scanner. The machine identifies(辨认)a product as soon as it's placed in front of a camera just by its shape and color, even if it has no bar code.

Babies sleep up to eighteen hours a day. Mrs. Thatcher and Napoleon both said they only needed to sleep three or four hours a night. Sleep—No one can live without it. But how much do we really need? 

Research by the National Sleep Foundation in Washington says that we all need eight hours' sleep every night. Scientists have found that people who sleep for less than six and a half hours a night are more often ill than people who sleep for eight hours. Going without sleep also increases the chance of serious illness. Workaholics who sleep for less than five hours often die young, and do less well at work. 

The scientists found that, on average(平均起来), adults sleep for seven hours a night, with 32% sleeping less than six hours. It also says that the idea that we need less sleep when we get older is completely untrue. "People have no idea how important sleep is to their lives," Dr. Thomas Roth, director of the Foundation says. "Good health needs good sleep."

"But not too much of it," says Professor Jim Home of Loughborough University. "Sleep is like food and drink," he believes, "You would always like to have a little bit more, but that doesn't mean you need it." Professor Home studied a group of people who could spend as many hours as they wanted in bed; after sleeping ten hours, they didn't find that they could get up easily either. And people who sleep for more than nine hours a night die younger than people who usually sleep for seven or eight! 

Meet Ozmo, the Window Cleaning Robot

The rise in skyscrapers worldwide is creating a high demand （需求）for window washers. Although a window cleaner earns as much as $35 an hour, the job is dangerous and accidents are not uncommon. Between 1983 and 2008, more than 70 window washers died while doing their jobs.

To take human employees out of danger, a company called Skyline Robotics has come up with a way to solve the problem. Ozmo, a window cleaning robot, will take over the dangerous job.

Ozmo was created by Avi Abadi and Yaron Schwarcz from Skyline Robotics.They were inspired （赋予灵感）when they looked up at some skyscrapers and noticed that some people were risking their lives to earn a living. Both thought that there must be a better way.

So Ozmo was born. The robot can be controlled by humans safely from the ground, as it uses machine learning and computer vision to clean windows at any height. While on duty, Ozmo will be sitting on the platforms hanging from the buildings. It cleans the dirt on windows using its arms and brushes. As it moves up and down the building，the robot can"skillfully"avoid ledges（窗台）and other obstacles（障碍物）that it will possibly meet.A 3D map of the building's surface is programmed into Ozmo's system to help the robot in such cases.

Before Skyline Robotics was founded in 2017, Avi and Yaron worked as window washers for a few weeks to get to know the job.

Aside from helping humans perform this job safely, Ozmo also helps Mother Earth. Instead of soap, it cleans the windows using only distilled water. （蒸馏水）

Do you know what the body mass index（BMI, 体重指数）is? According to the National Health Service, BMI is a measure（测量方法）that uses your height and weight to work out if you are fit. 

Some cities in China have included BMI in the PE test for the high school entrance examination, or zhongkao. For example, Beijing in 2021 announced that BMI officially became a subject of the PE test for the zhongkao. Chengdu and Shanghai have also started similar actions. BMI in cities like Xiamen, although not included in the zhongkao, still plays a role in regular PE tests. 

Zhang Yanshu is a grade 8 student from Beijing Chaoyang Foreign Language School. He used to be overweight. "It was this summer that I decided to work on my BMI, " Zhang said. He started by running with his dad, and soon took a stamina（体能）course which trained him for different things like running, pull-ups and so on. "I think BMI and the events for the exam go well together. When I practice the events, my BMI gets better; when my BMI gets better, I feel more energetic（精力充沛的）doing the events. "

Zhang also paid much attention to his diet. "I ate brown rice instead of white rice, and chicken for meat most of the time, " he said. "It was for sure sad. " His BMI reached a normal level after four months of effort（努力）"My health and willpower（意志力）have seen a big improvement. "

Chen Kaifei, 14, also from Beijing said that BMI is also a problem for students who are too thin, and has caused some"figure anxiety（身材焦虑）"among students. "However, mostly I think it has a good influence, " Chen said. "Everyone has a better understanding of their body and health conditions, and I started to care about my diet and lifestyle every day, simply to keep my BMI at a good level. "

We are all busy talking about and using the Internet, but do we know the history of the Internet?

 Many people are surprised when they find that the Internet appeared in the 1960s. {#blank#}1{#/blank#} And the net among computers didn't work well. If one computer in the net broke down, then the whole net stopped. {#blank#}2{#/blank#} Inshould be good enough to be used by many different computers.

{#blank#}3{#/blank#} But, in the early 1970s, universities, hospitals and banks were allowed to use it, too. However, computers were still very expensive and the Internet was difficult to use. {#blank#}4{#/blank#} Scientists had also developed software that made" surfing" the Internet more convenient.

Today it is easy to get online and millions of people use the Internet to chat with each other every day. {#blank#}5{#/blank#} The Internet has now become one of the most important parts of people's life.