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    Have you ever had dreams about building a robot? Or putting together a spaceship? Or even seeing your face made out of chocolate? Done. All you need is a 3-D printer.

    The possibilities of 3-D printing seem endless(无穷尽的）.All the user has to do is to design an object on the computer and choose a material to print in. The printers print in hundreds of different materials including glass, sugar and even skin! When the user presses(按）“print", the 3-D printer spreads the materials layer(层）by layer and like magic the object is produced.

    The first 3-D printer was invented in 1986 by an American, Charles Hull. But 3-D printing has only become cheap enough recently for most people to use. Designers now use 3-D printing to create unusual things. The Dutch artist Dirk Vander Kooj prints furniture made from old fridges. And doctors have used 3-D printing to print human body parts! The Telegraph reported in February that scientists from Cornell Medical College even printed a man-made ear.

    But like a lot of new technologies, if 3-D printing gets into the wrong hands, it can be dangerous.

    In 2011 a group of four men in the US used 3-D printing to produce ATM skimmers(提款机盗刷器).These were placed on an ATM and stole over $400,000 from users of the ATM. It is terrible to think that criminals like them might one day use a 3-D printer to print a gun.

    But for better or for worse, 3-D printing has been put into use. In a few years, you'll probably be wondering how you could ever live without your 3-D printer!

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    Different weather makes people feel different. It influences health, intelligence (智力) and feelings.

    In August, it is very hot and wet in the southern part of the United States. People there have heart trouble and other kinds of health problems during this month. In the Northeast and the Middle West, it is very hot at some times and very cold at other times. People in these states have more heart trouble after the weather changes in February or March.

    The weather can also influence intelligence. For example, in a scientific report, IQ (智商) of a group of students was very high when a very strong wind came, but after the strong wind, their IQ was 10% below. The wind can help people have more intelligence. Very hot weather, on the other hand (另一方面), can make it lower. Students in many schools of the United States often get worse on exams in the hot months of the year (July and August).

    Weather also has a strong influence on people's feelings. Winter may be a bad time for thin people. They usually feel cold during these months. They might feel unhappy during cold weather. But fat people may have a hard time in hot summer. At about 18 ℃, people become stronger.

    Low air pressure (气压) may make people forgetful People leave more bags on buses and in shops on low-pressure days. There is a "good weather" for health. People feel best at a temperature of about I8℃.

    Are you feeling sad, tired, forgetful, or unhappy today? It may be the weather's problem.

    Sophia is a robot in Saudi Arabia. She made history at a meeting that was held in the country on Oct 25. On that day, she became the first robot in the world to get citizenship (公民身份), according to The New York Times.

    In the future, Sophia may have the same rights as a human Saudi Arabian citizen.

    Sophia looks like a human woman. In 2015, a US company built her and gave her an artificial intelligence system (人工智能系统). This means Sophia can talk and act like a human. She also has the ability to learn from people, books and the Internet.

    "I will do my best to make the world a better place," Sophia said at the meeting.

    But not everyone is happy with Sophia's citizenship. Some think robots like her could be dangerous. They could become enemies of humans if they go out of control.

    For this, Sophia said she also had values like wisdom and kindness. "Don't worry, if you're nice to me, I'll be nice to you," she said.