Electric cars may seem like a recent invention but they have been around for years. In the early 1990s there were ______ electric cars on the road than gasoline cars, because at that time, gasoline was expensive compared with other fuels (燃料), electric cars were more popular.

When gasoline prices dropped and new ______ on gasoline cars were developed, electric cars were out of date. Gasoline cars became more popular ______, because they could go farther without stopping.

During the 20th century, gasoline cars got bigger, heavier and faster. They needed more fuels, and it ______ more air pollution. For years, the car makers didn’t worry about pollution. They didn’t worry about how much gasoline cars used, either. But when people began to ______ that there was not enough oil on the earth, they asked car makers to produce more efficient and less polluting cars.

One ______ of solving the problem was a “hybrid” car (混合动力车), one that ran partly on gasoline and partly on electricity. Hybrid cars became popular in the 2000s because gasoline prices went up while prices of hybrid cars went ______.

An all-electric car uses no gasoline. The problem, however, is that car batteries need to be recharged (充电). That makes electric cars not so ______ for long journeys. So many people are not pleased with it. The government and car makers are working together to ______ safe, cheap and useful electric cars. When more people have these electric cars in the future, a gasoline station may ______. We hope that our life will be better.