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In many big cities in the world，the overuse of cars is thought to be one of the major causes of air pollution．What will cars be l 1 in the future?
Some experts think that today’s cars are in trouble b 2 they use too much petrol(汽油)．They say the car of the future will be much，much smaller．The car of tomorrow will be m3 without a motor or air conditioning．It’ll have no radio and no lights．Tomorrow’s car will be an o 4 air car with no doors or windows．It needn’t have a pollution control system because it w 5 use petrol．In fact，this new car will be pushed by the driver’s feet．Very few people will be killed in accidents，because the top s 6 will be five miles per hour．However，we are also warned not to ask for pretty c 7 ，because the ears will come in grey only．
Other car experts do not hold the same idea．They are s 8 that the future will be happier．They think that all our problems will soon be solved by car companies with the production of the Supercar．Tomorrow’s car will be bigger，faster，and more comfortable than b 9 ．The Supercar will have four rooms，TVs，running water，heat，air conditioning，and maybe a swimming pool．Large families will travel on l 10 trips comfortably．If petrol is in short supply(供应)，the Supercar will run on water．
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