Recent research from the Pew Internet Project suggests that 90% of Americans aged from 12 to 17 use the Internet, and 51% of those teens use social networks. However, there are many possible problems with social networking sites and the teenagers who use them.

Apart from the social advantages, social networking sites can be used to record school research, develop artistic talents and experiment with other forms of subject creation. They provide a way to communicate with others who share the same interests and to get helpful advice on ongoing projects.
Along with these advantages come some dangers. For example, most social networking sites are open to all, especially MySpace, which is the most popular social network among teens in America. It means that they could be put in unpleasant and frightening situations.
A greater danger is that teens may become objects of the people with secret purposes. The secrecy of some social networking sites makes it easy for dangerous people to find young teens and invite them into dangerous conversations. It's easy for them to pretend as teens and draw children into dangerous real-world communication as well. Then further hurt might be on its way.
Another danger is identity stealing, which can happen when teens share too much information about their names, dates of birth and locations.
Therefore, it's very important to make sure teens are safe when they use social networks.
Many of the same rules that work for online chat work for these sites:
※Don't use your real name.
※ Don't give out personal information to people you don't know. A last name and a town are enough for a bad guy to find where you are.
※ Don't believe that people are who they say to be.
※ Immediately end any communication that makes you uncomfortable and report it to a parent.
Only if you are sure of your safety, can you enjoy the fun brought by social networking. Besides, trying to deal with all problems on your own can lead to terrible results. Remember, asking your parents or school officials for help doesn't mean you are unable to do anything but wiser than many others.

    Have you ever seen the movie. Big Hero 6 ? Baymax(大白) is a main character in the movie. He's a friendly big robot that looks after people's health. If there is a robot like Baymax in our real life， people will get more benefits. The robot will be especially helpful in caring for the old. The health of old people needs greater monitoring and care.

    Scientists in America are now working to make Baymax a really(实现)- Actually. They have already produced some health care robots. These robots provide brain video games to improve people's memory. The garner can help the old remember things for longer. Besides， these  provide special app (应用程序） to help the old manage their health at home. The apps can check  the old people' heart rate (心率) and tell them to take their medicine on lime. The apps can also record their daily activities. Such collected information helps doctors discover the cause of an illness faster and more correctly. But the health care robots are't as clever as Baymax yet.

    Nowadays，scientists are working on improving the health care robots. They pope the robots can produce electricity by walking across the floor. If they succeed. batteries will not be needed. They also hope the robots communicate with humans in the daily life so to make people happier and healthier.

    Scientists are trying to realize these dreams. Like Baymax， these health care robots may save people's lives in the future. We are looking forward to them.

    Soon computers and other machines will be able to remember you by looking at your eyes! The program works because everyone's eyes are different. So in the future you won't have to remember the number of your credit card when you want to use a machine or take money out of a bank. You'll just have to look at the machine and it will be able to tell who you are.

    The eye-recognition（眼睛识别）program has already been tested in shops and banks in the USA, Britain, Spain, Italy and Turkey. Soon this technology will take the place of all other ways of finding out who people are.

    Eye-recognition is a course of recognizing iris（虹膜）, which includes the following steps. First, a kind of machine needs to collect different examples of one's iris from his eyes and store them. Second, when this person goes to the bank to take out money, this machine will have iris feature extraction（采集）. Then, this machine will compare the examples kept in it with iris feature extraction. Once the examples and the feature extraction are the same, this person will be identified, and he will take out the money from the bank successfully.

    However, scientists are also working on other systems. Machines will soon be able to know you from the shape of your face or hand or even your smell! We already have machines that can tell who you are from your voice or the mark made by your finger.

    Eye-recognition is better than other kinds because your eyes don't change as you get older, and don't get dirty like hands or fingers, and even twins have different eyes. So the eye-recognition program can be up to 94% correct, depending on how good the technology is. However, some other programs may only be 51% correct now. In Britain, it was found that 91% of people who had tried it said that they liked the idea of eye-recognition.

    In the future your computer will be looking you in the eye. So smile!

    Have you ever imagined going to other countries without your paper Passport? That will soon come true. And your paper passport will become history. You may use their new kind of passport

    It's reported that Australia will be the first country to use the cloud passport. With the cloud passport, you don't have to take a paper passport with you all the time. The cloud passport will have your name, photos and other information. And if you go to other countries, you can just check the information on the computer.

    When you take a paper passport with you, you might lose it. But with the cloud passport, you don't have to worry about that.

    Do you think the cloud passport is a great idea? Perhaps you will have it in the future, too.

    The kiwi lives only in New Zealand. It is a very strange bird because it can not fly.

    The kiwi is the same size as a chicken. It has no wings or tail. It doesn't have any feathers(羽毛)like other birds. It has two feet and each foot has four toes. Its mouth is very long.

    A kiwi likes to have a lot of trees around it. It sleeps during the day because the sunlight hurts its eyes.

    It can smell things with its nose. It is the only bird in the world that can smell things. The kiwi's eggs are very big. There are only a few kiwis in New Zealand now. People never see them. The government says that people can't kill kiwi. New Zealanders want their kiwis to live.

    There is a picture of a kiwi on New Zealand money. People from New Zealand are sometimes called kiwis.

    An atlas is-a book of maps. Atlases are made with different kinds of information about different parts and areas of a country or the world. They are prepared for desk use or travel use.

    Desk atlases are made for different groups of people with different needs. For example, students may use desk atlases to help learn Geography, and other people may use desk atlases to study a place. A popular type of the latest atlas shows the recent fact of the world. New atlases are often carefully produced to help people learn about the changes, such as name changes, boundary(界) changes and other important new information. A desk atlas can also have some different maps of the same place. For example, an atlas may include maps showing population and important products of a place.

    Travel atlases usually show the information about both natural and man-made features(特点). So it is not surprising to find universities, airports, forests, rivers, roads as well as cities, towns and villages in them. A travel atlas is often the first thing people need when they want to start a trip in a strange place.

    It often has a map of a whole country, and a map with more special information of each important place in the country. Take the atlas of the United States as an example, it often has a map of the whole country and then a map of each of the fifty states.

    A travel atlas may also point out the beautiful natural places. In the USA, the atlas may include national parks such as the Yellowstone National Park and some others to show the beauty of nature and interesting places to tourists.