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    For many smart phone users, especially young people, scanning QR Codes（二维码）has become a new and convenient life style these days. In fact, the QR Code was created in Japan in 1994, but until 11 years later, it was first used in China. It soon became popular around the country. The QR Code is much-loved because it provides a way to get to website more quickly. By scanning QR Codes, people can do lots of things, such as adding new friends, getting information, downloading Apps, shopping and so on. As for the shopping websites, there are usually more sales, including coupons（优惠券）for the phone users. The QR code is so common that people can scan them everywhere. We interviewed 100 people, and here are the results.

    Animals are our friends. We can find different animals here and there. Some animals live in big forests(森林) and some animals live with man.

    Animals can help us a lot. Elephants can do some heavy work for us. And dogs can look after the home. The kids like dogs very much. Cats are women's favorite animals.

    We can eat their meat. We can make coats and shoes with their skins(皮). We can get milk from them. So man can't live without animals.

    As space science develops, man has learned more and more about space. Space is not only amazing but also dangerous. While working in space, spacemen are facing danger as well as success.

    Scientists have found out that the radiation(辐射) is the greatest danger to spacemen in space. When spacemen are working in space, they are in danger of the radiation from the sun and other stars, which is bad for their health. The harm of the radiation won't be found until their children even grandchildren are born. Some special medicine may work a little, but no really effective medicine has been found so far. Space rubbish is also thought to be a great danger to spacemen. It's reported that there were 9,000 man-made things flying in space. About 30% of these are satellites, 10% are spaceships, and the rest are space rubbish. An explosion(爆炸) in space in 1999 made a cloud of 300,000fragments, each at least 4mm in size. A small piece of these even knocked a spaceship window and caused some damage(损坏).

    Scientists are watching and reporting any possible danger all the time. They are working to deal with space rubbish. Although space is really dangerous, it interests many people on the earth. In the near future, it may become possible for people to spend a few days in a space hotel. People may even choose to leave the earth and live in space in a few years. So scientists are doing everything they can to help improve the space environment.

    What can 3-D printers*make? They can make lots of things, such as toys and car parts. But what about a house? In the Netherland 3-D printed houses will soon come into life, according to The Guardian

The Netherlands is the first country to have this technology*.

    Scientists plan to build five houses with 3-D printers. The first house will be finished by the end of 2019. It will be a house with three bedrooms. For the first house, only the walls will be 3-D printed. A 3-D printer will print it with a special cement. The printer will print it layer upon layer to build the walls. After that, workers will make the wall stronger.

    By the time they start working on the fifth house, the scientists hope that most parts of the house will be made with 3-D printing. Even the windows can be made with a 3-D printer.

    The 3-D printed houses have many advantages. For example, they use less cement than traditional houses. It can help save a lot of money. Also, 3-D printing can make buildings in almost any shape*. Traditionally-built homes usually come in just a few shapes