听力原文： What kind of car we will drive by the year 2020? Rather different from the type we know today. With the next decade bringing greater change than the past 50 years, people who will design the models of tomorrow believe that environmental problems may well accelerate the pace of the car's development. The vision is that of a machine with 3 wheels instead of 4, electrically-powered, environmentally clean and able to drive itself along intelligent roads, e quipped with built-in power supplies. Future cars will pick up the fuel during long journeys from a power source built into the, road, or stored in small quantities for traveling in the city. Instead of today's seating arrangement two in front, two or three behind, all facing forward, the 2020 car will have an interior with adults and children in a family circle. This view of future car is based on a much more sophisticated road system. Cars will be automatically controlled by a computer. All the driver will have to do is to say where to go and the computer will do the rest. It will become impossible for cars to crash into one another. The technology already exists for the car to become a true automobile. What is the designer's vision of the cars of tomorrow?