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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.

      What would the world be like if cars could drive themselves? Imagine seeing an empty car passing by on its way to pick up its owner, or a car full of passengers who are reading, listening to music or even sleeping. But none of them are worried about the road ahead.

      Well, all of this could be the future of driving. There are several companies, including Google, working on driverless cars. So far, no Google self-driven car has gotten a traffic ticket, but some of them have been in accidents when other cars hit them.

      These cars are now still in the testing stages. But, if the tests are successful, these electric self-driven cars could be put into use very soon.

      The cars already have many features（特点）allowing them to take the place of drivers during certain situations. Some features include cars being able to park themselves, or slow down when they notice objects close by. They can also control the speed if there are dangerous conditions.

      Scientists and engineers believe, with the help of wireless signals, cameras and GPS, we are now at a stage where creating a safe self-driven car might be possible.

      The cause of deadly road accidents is usually careless drivers or dangerous conditions. The self-driven car may be able to prevent these. However, some people do not like the idea. American lawyer Whit Drake, for example, doesn't believe these cars are safe. He thinks that technologies can also be mistakes.

    Teenagers are known for being creative and full of new ideas. Let's have a look at these teenage inventions that might change the world.