When it is time for a new car, choose a more fuel efficient vehicle.

该买台新车时，选辆最省燃料的吧。

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Diesel engines are the most fuel efficient vehicle power source available.

柴油发动机是现有燃油效率最高的机器。

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When you are choosing a vehicle and you have selected the most appropriate class of vehicle for your needs, choose the most fuel efficient vehicle in that group.

当你在选择一种交通工具或已经选择了能够满足需要的最合适的一种交通工具的时候，要选择那一类当中最高效节能的那一个。

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Ahead of next year's challenge, the team are planning to upgrade the engine in their energy-efficient vehicle.

BBC: Car built by Wiltshire pupils clocks 2,000 mpg

Kingdown School in Warminster took first place in the schools race to find the most energy-efficient vehicle at Mallory Park track, near Leicester.

BBC: Car built by Wiltshire pupils clocks 2,000 mpg

It educates the consumer on how much they are paying for having a low-MPG car and encourages them to get into a more efficient vehicle.

CNN: Commentary: Why 'Cash for Clunkers' works