I think, though, that even in the USA, ethanol is still only used as an additive to gasoline, or petrol.

不过我认为，即使在美国，乙醇仍然只用作汽油的添加剂。

youdao

Ethanol, which is used mainly as an additive to petrol, is not a particularly good fuel: it offers only about two-thirds as much energy as petrol and can corrode pipelines and car engines.

主要用来添加在汽油中的乙醇，并不是非常好的燃料：其能量密度只有汽油的三分之二，而且会对汽车引擎和管路造成腐蚀。

youdao

At the same time, the high price of oil is fuelling demand for ethanol, which is used as both a substitute for and an additive to petrol.

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Ethanol, which is used mainly as an additive to petrol, is not a particularly good fuel: it offers only about two-thirds as much energy as petrol and can corrode pipelines and car engines.

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MTBE, an additive mixed with petrol to reduce air pollution, had caused it to leak into water supplies.

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