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A science fiction flying car looks like a normal car, but it is an aircraft (飞行器) that anybody can fly directly from any place to another without using roads or runways. Science fiction writers have written about flying cars for a long time. But now flying cars will soon fly out of the world of science fiction into our real world. And the dream of the science fiction writers will soon come true.

    The first-known sky car is the FSC-1. The FSC-1 looks like an expensive sports car. You can drive the FSC-1 on the road like a normal car. If you touch a button, its wings and propeller (螺旋桨) fold out and then it can take off, fly and land as an airplane. The owners of the FSC-1 can choose if they want to drive or fly.

Another flying car or sky car is the Moller Skycar M400. Although you can't drive it on the roads, it is small and easy to fly and can take off and land like a helicopter (直升飞机). Urban Aeronautics' X-Hawk is another type of sky car. It is expected to be available for about $3 million.

    Just like any new technology, flying cars have taken a long time to be developed. But some experts think the technology is far from what people imagine when they are sitting in traffic. It still needs to be improved.

Dreams may be more important than sleep. Some people don't need much sleep. But we all need to dream, scientists say.

    Dreams take up about one quarter of our sleeping time. People have several dreams each night. Dreams are like short films. They are usually in color. Some dreams are like old films. They come to us over and over again. That may be because the dreamer is worrying about something. Dreaming may be a way of trying to find an answer.

    Some people get new ideas about their work from dreams. They could have been thinking about their work all day. These thoughts can carry over into dream. Sometimes we wake up with a good feeling from a dream. But often we can't remember the dream.

    Dreams can disappear quickly from memory. Too much dreaming can be harmful. The more we sleep, the longer we dream. The mind is hard at working when we dream. That is why we may have a long sleep and still wake up tired.

    Have you noticed your life becoming a little easier? Now, when you go to a certain shopping mall, you can enjoy its free Wi-Fi there. When you want to take a taxi, you can book one with your phone. In fact, all these can be seen as the basic parts of a smart city.

    The idea of a smart city was brought up by US company IBM in 2010. Generally, a smart city is a city that uses digital technologies such as the Internet to improve city planning, save money and resources, and make our life convenient. How smart can a city be? Here are great examples that we can learn from.

    In 2009, Dubuque became the first smart city in the US. The city used smart water meters to take the place of traditional water me tens. They can detect (探测) water waste and leakage (泄漏) and send data to let the house owner know. The same system is used for other city resources like electricity and natural gas. In this way, people know how they use their resources and are glad to help reduce waste.

    Santander in Spain also gives us a look at the future. If people point a phone toward a nearby bus stop, the phone immediately shows all bus lines that serve the stop as well as their arrival times. The government organized a research team and provided an App (应用程序) that collects data on almost everything: light, temperature, and the movements of cars and people. Opening the App near a supermarket provides immediate information on special offers.