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    Astronauts (宇航员) face many problems when living in space stations. One of them is food. People on Earth put together all the meals first and then send these meals to space stations by space shuttle. Because the food has to last a long time (sometimes up to three months), people have to store a lot of it in cans. The space station does not have a fridge, but it has a cool room to keep fruit and vegetables fresh. Astronauts also eat many other foods such as dried meat that do not need special care.

    Without the help of gravity sitting down to eat can be difficult. Astronauts sometimes have to fix themselves to the wall while eating. They also have to be very careful so that food does not float away.

    Robots seem to be getting cleverer and cleverer. Here are four examples.

    Personal planes which can take off noiselessly from the back garden will be possible within two years.

    Lilium Aviation is inventing an electric two-seater airplane which  takes just 20 hours to learn to fly and can travel at speeds of  250mph.More importantly, the small plane, which weighs just 25kg, can take off vertically which means it does not need to fly from an airport, but could be parked outside a house or in a garden. The company says the design will “open the door to a new class of simpler, quieter and environmentally friendly planes” and will be possible from 2018.

    “Our goal is to develop an airplane for use in everyday life,” said Daniel, CEO and one of the company's four founders. "We are going for a plane that can take off and land vertically and does not need the difficult and expensive infrastructure of an airport.

    Although helicopters offer a choice, they are very noisy and difficult to fly and require expensive licenses. They also have no backup if the rotor fails, making them costly to build and keep. While firstly limited to airfields, the Lilium airplane will eventually take off vertically from almost anywhere – even from back gardens – it needs only an open flat area of 50 ft. by 50ft (15 m x 15m).

    The plane is classed as a Light Sport Aircraft for two users, with the pilot's license requiring 20 hours' minimum training – almost like taking a driving license. It is intended for fun flying during daylight, in good weather conditions and in least crowded airspace up to 3 km altitude. The airplane would have to follow the same flight laws as helicopters.

    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.

    Waste can be seen everywhere in the school. Some students ask for more food than they can eat and others often forget to turn off the lights when they leave the classroom. They say they can afford these things. But I don't agree with them.

    Waste can bring a lot of problems. Although China is rich in some resources(资源), we are short of others, for example, fresh water. It is reported that we will have no coal(煤) or oil to use in 100 years. So if we go on wasting our resources, what can we use in the future and where can we move? Think about it. I think we should say no to the students who waste things every day. Everybody should stop wasting as soon as possible.

    In our everyday life, we can do many things to prevent waste from happening, for example, turn off the water taps when we finish washing, turn off the lights when we leave the classroom, try not to order more food than we need, and so on. Little by little, everything will be changed. Waste can be stopped one day, if we do our best.

    In our daily life, robots are often found to do work that is too dangerous, boring, difficult, or dirty. And we often see kids play with toy robots.

    But what exactly is a robot? There are some important characteristics(特征) that a robot must have. These characteristics might help you to decide what is and what is not a robot. It will also help you to decide what you will need to build into a machine before it can be considered as a robot. A robot has these important characteristics.

    Sensing First of all, your robot would have to be able to sense the environment around it. 

    Give your robot sensors (传感器): light sensors( eyes ), touch sensors (hands), chemical sensors(nose), hearing sensors(ears) and taste sensors (tongue).

    Movement A robot needs to be able to move around its environment.  It can move on wheels, walk on legs or be driven by small engines(发动机). A robot can move either the whole body or just parts of it.

    Energy A robot needs to be able to power itself.  Some robots might power itself with sunlight, some might with electricity, while others with the battery(电池). The way your robot gets its energy will depend on what your robot needs to do.

    Intelligence A robot needs some kind of "smarts". A programmer is the person who gives the robot its "smarts". The robot will have to have a certain way to receive the program so that it knows what it is to do.