Imagine the situation. You are driving in a village or on a mountain. You have no idea whe

Imagine the situation. You are driving in a village or on a mountain. You have no idea where you are. You passed the last house two hours ago. Then your car doesn’t work. It is night and it is cold. You have no mobile phone. What do you do? Well, next time take a GPS with you. This invention may be able to help you. It is used for finding your position(位置) with the help of satellites (卫星). A GPS can’t start your car, but at least you will know where you are.
GPS, which means Global Positioning System(全球定位系统), is a small radio receiver. It looks like a mobile phone. You can hold it in your hand, or put in your pocket. It is sometimes put into a watch or a telephone. We also find a GPS in cars, planes, or boats. Some of them have electronic maps, so you know where you are. For example, in a city they can tell you the name of the street.
There are three parts to GPS. The first part is the receiver. You can hold it in your hand, or have it fixed into your car, plane, etc. The second part is a group of satellites going around the Earth. The receiver communicates with at least four of the satellites and calculates its position. The third part of the system is a network of ground stations all over the world. They control (控制) the satellites and make sure they are working well.
Some people think that in the future the GPS will be as common as the mobile. They are becoming better and cheaper. There are also new uses for the GPS. Perhaps they will become like watches. Everyone will have one and you will never be lost again.
【小题1】According to the passage, with the help of the GPS, people .A．can’t be lost in a new cityB．can’t find their way in different countriesC．can learn about the culture of an unknown placeD．can spend the least time getting to another place【小题2】We can learn from the passage that .A．there are three parts to the GPSB．a GPS can’t be put into a watchC．a GPS can help you start your carD．the GPS are becoming more and more expensive【小题3】The underlined word “They ” in paragraph 3 means “ ”.A．ReceiversB．GPSC．SatellitesD．Ground stations【小题4】What can we infer(推断) from the passage? A．All GPS devices have electronic maps.B．People in many countries will use the GPS for free.C．The receiver of the GPS communicates with at least five of the satellites.D．The GPS will become more and more common in everyday life.A

(答案→)A 解析：这是一篇富有科学的短文。短文介绍了一种高科技产品----全球定位系统。全球定位系统由三个部分组成-----接收器、卫星群、网络。它能正确确定你所在的位置，让你不再迷路。她已经广泛应用于汽车、飞机、轮船等交通工具，将来它还会像手机一样普及在日常生活中。【小题1】细节理解题。短文最后说到：Everyone will have one and you will never be lost again.每个人都会有一个全球定位系统，这样你再也不会迷路了。故选A。 【小题2】细节理解题。短文第二段说：There are three parts to GPS.全球定位系统有三个部分。所以应该选A。【小题3】细节理解题。这个题目要结合上文理解，短文说：The third part of the system is a network of ground stations all over the world. They control (控制) the satellites and make sure they are working well.第三部分是全世界的地面基站网络，他们控制着卫星确保卫星正常运转。所以这里的they是指地面基站网络。故选D。【小题4】细节理解题。从短文最后一段可以看出全球定位系统将会广泛应用于日常生活中。Some people think that in the future the GPS will be as common as the mobile.人们认为将来全球定位系统会像手机一样普遍。Perhaps they will become like watches.也许他们会像手表。所以选D。

我明天再问问老师，叫他解释下这个问题