Where do cars get their energy from? For most cars, the answer is petrol. _____21____some cars use electricity. These cars have ____22____motors that get their power from large batteries.

In ____23____, there are even cars that have____ 24____ an electric motor and a petrol motor. These types of cars are ____25____ hybrid(混合)cars.

Most people tend to think of electric cars as a new ____26____, but they have been around for a long time. In the ____27____ 19th and early 20th centuries electric cars were common because the technology for petrol engines was not very advanced.

But ____28____ the petrol engine became easier to make and more powerful, this type of engines became the most ____29____. Interest in electric cars was high in the 1970s and 1980s because ____30____ became very expensive.

Recently, electric cars have again become well-liked because people want cars that pollute ____31____ . Electric cars are better than petrol cars ____32____ several ways. The biggest benefit is reduced pollution.

In areas ____33____ there is a high percentage of electric cars, pollution is not that serious. The second benefit of electric cars is a ____34____in the dependence on foreign oil.

Several countries don't want to ____35____on oil from other countries. Since electric cars can run on electricity from coal or nuclear power stations, there is less need to import oil.

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