A kind of little cars may some day take the place of today's cars. If everyone drives such cars in the future, there will be less pollution. There will also be more space for parking cars in cities, and the streets will be less crowded. Three such cars can fit in the space now needed for one car of the usual size.
The little cars will cost much less to own and to drive. Driving will be safer too, as these little cars can go only 65 kilometres an hour. The cars of the future will be fine for getting around a city, but they will not be useful for long trips. Little cars will go 450 kilometres before needing to stop for more gas (汽油).
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, fast cars and other roads will be needed for the slower, small ones.
