Fuel (in vapor form), air (oxygen), and an ignition temperature are necessary for combustion. No combustion can occur without all three of these essentials.

燃料(以蒸汽形式存在)、空气(氧气)和点燃温度是燃烧的必要条件，不具备这三个必要条件不可能燃烧。

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When jet fuel burns, it releases both water vapor and microscopic particles of exhaust.

当飞机的燃料点燃的时候，在它的尾气中会发出水蒸气和微小的粒子。

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Gasoline is a fuel whose vapor is readily explosive.

汽油是一种燃料，其油气容易爆炸。

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By 2020 or so, depending on the progress of fuel cell technology, the last of the island's 9, 500 gasoline cars will be gone and only water-vapor-emitting fuel cell autos will remain, according to Taniguchi's plan.

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If you oxidize any hydrocarbon, you generally produce heat, carbon dioxide, and water vapor, assuming a relatively pure fuel source.

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If, on the other hand, you were to buy summer gasoline and try to store it until winter, you might find yourself having problems getting the fuel to ignite, due to the lower vapor pressure.

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