Most cars run on gas. Gas cars work very well. But there is a problem. Cars that run on gas make the air dirty. The dirty air is not good for people, animals or trees. Gas cars make the air dirty for all living things. What can we do? We can drive electric cars!
Electric cars do not use gas. These cars do not make the air dirty. These cars have batteries that power their motors(马达). The batteries can be charged（充电）many times. They can be used again and again. This makes electric cars great. But electric cars have problems too. They are slower than gas cars. They are also very quiet. This means that some people can't hear them when they go by. They may not think a car is coming. Sotheyhave to be careful.
People are looking for ways to make electric cars better all the time. Maybe one day all cars will be electric. That would be much better for the world.
