Imagine the situation. You are driving along a desert or on a mountain. You have no idea where you are. You passed the last house two hours ago. Then your car breaks down. 小题1: You have no mobile phone. What should you do? Well, next time take a GPS with you. This invention may be able to help you. 小题2: It can find your position to within 20 metres. A GPS cannot start your car, but at least you will know where you are. GPS, which means Global Positioning System, is a small radio receiver. It looks like a mobile phone. 小题3: We also find GPS devices in cars, planes, or boats. Some of these devices have electronic maps, so you know where you are. 小题4: Some people think that in the future the GPS will be as common as the mobile. 小题5: here are also new uses for the GPS. Perhaps they will become like watches. Everyone will have one and you will never be lost again.
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