单选题 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____请作答此空______ 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 l970s 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.