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Now cities are full of cars. Some families even have two or more cars. Parking (停车) is a serious problem, and it causes the traffic around the cities. Something will have to be done to change them. What will the cars of tomorrow be like?

Little cars may some day take the place of today’s big cars. If everyone drives little cars in the future, there will be less air pollution. There will be more space for parking cars in cities, and the streets will be less crowded. Three little cars can park in the space now needed for a car of the usual size. The little cars will cost less to own and to drive. Driving will be safer, too. What’s more, these little cars can go about 65 kilometers an hour.

Little cars in the future will be fine for getting around a city, but they will not be suitable for long trips. If big cars are still used along with the small ones, two sets of roads will be needed in the future. Some roads will be used for the big and fast cars, and other roads will be needed for the small ones.

【小题1】________is a big problem for people who have cars.
【小题2】Little cars in the future may bring ________ pollution into the air.
【小题3】A car of the usual size can park ________ in the space now.
【小题4】The little cars will be not suitable for ________.
【小题5】If all of us drive little cars in the future, our life will be ________.