The airline's biggest headache is the increase in the price of aviation fuel.

令航空公司最头疼的问题是航空燃料价格的上涨。

《柯林斯英汉双解大词典》

Pathetic attempts were made to make aviation fuel by boiling and distilling pine roots.

他们试图通过煮和蒸馏松树根为航空提供燃料，最终这只是糟糕的尝试。

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So desperate was Japan, it even tried to make aviation fuel by distilling pine tree roots.

走投无路，绝望透顶的日本，甚至企图通过蒸馏松树根制造航空燃油。

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But for anything much bigger, the energy density of aviation fuel still looks to be unbeatable.

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And after the capital cost of the airplanes themselves, aviation fuel is the major cost of any airline.

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General aviation fuel taxes are the best way for the industry to contribute necessary revenues to federal coffers.

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