听力文摘：最快的车是什么？（在线收听）

What Makes Hybrid Cars So Efficient?

最快的车是什么？

Don :Hybrid cars are known as hybrids because they use an electric motor to augment the performance of a small, efficient gasoline engine. But this isn’t the only reason hybrids are more efficient than gas-powered cars. Did you know that Hybrid cars are made of lightweight materials, so they require less energy to accelerate or drive up a hill?

混合动力汽车简称“hybrids”，因为这类汽车采用电动马达增加小而高效的燃气发动机动力。但这并混合动力汽车比燃气汽车高效的原因之一。你知道吗？混合动力汽车选用轻型材料，所以加速或爬坡需要的动力相对更少。

Yael: You know, Don, maybe you just need to trust that hybrid cars are interesting enough on their own. I mean, did you know that some hybrids rely on a process known as regenerative braking to recharge their batteries. You see, when you brake, you remove energy from your car, which normally just dissipates in the form of heat. In some hybrids, though, the electric motor is used to slow down the car, at which time it also acts as a generator so it can divert some of that energy back to the batteries. And did you know? In hybrids, instead of idling, the gas engine turns itself off, and you get power from the electric motor and batteries. Also, hybrid cars’ aerodynamic design and special tires reduce both air drag and drag against pavement, which also increases efficiency.

冬, 要知道，混合动力汽车本身就很有趣。我的意思是，你知道吗？一些混合动力汽车依靠“再生式制动”来完成充电。一般的汽车刹车时，通常以散失热量的形式损失汽车动力。但是，混合动力汽车的电动马达让汽车减速，同时将这部分能量转换成电能，充当发动机的功效。另外，你知道吗？混合动力汽车发动机没气了，汽车并不会空转，而是由电马达继续供能。此外，混合动力汽车采用气流设计和特殊轮胎，从而减少空气阻力和路面摩擦阻力，这也是混合动力汽车跑得快的原因。

D: Cool!

太赞了！