But when the politician or the engineer refers to oil, he almost always means mineral oil, the oil that drives tanks, aero planes and warships, motor-cars and diesel locomotives, the oil that is used to lubricate all kinds of machinery.

但是，政客或工程師談到油的時候，他所指的幾乎總是礦物油。這種油可以用來開坦克，開飛機，開軍艦，開汽車，開柴油機

車，可以用來潤滑各種機械。

This is the oil that has changed the life of the common man.

就是這種油改變了普通人的生活。

When it is refined into petrol it is used to drive the internal combustion engine.

這種油經(jīng)過提煉變成汽油以后，可以用來開動內(nèi)燃機。

To it we owe the existence of the motor-car, which has replaced the private carriage drawn by the horse.

就是因為有了這種油，我們才能用上汽車，以代替馬車。

To it we owe the possibility of flying.

就是因為有了這種油，我們才有可能飛行。

It has changed the methods of warfare on land and sea.

它還改變了陸戰(zhàn)和海戰(zhàn)的方法。

This kind of oil comes out of the earth.

這種油來源于地下。

Because it burns well, it is used as fuel and in some ways it is superior to coal in this respect.

它因為易于燃燒，可以用作燃料，而且在這方面比煤還有若干優(yōu)越之處。

Many big ships now burn oil instead of coal.

現(xiàn)在許多大輪船就燒油而不燒煤。

Because it burns brightly, it is used for illumination; countless homes are still illuminated with oil-burning lamps.

它因為燃燒時非常明亮，也可以用來照明，許多家庭現(xiàn)在仍靠油燈照明。

Because it is very slippery, it is used for lubrication.

它因為非?；瑵櫍钥梢杂米鳚櫥瑒?。

Two metal surfaces rubbing together cause friction and heat; but if they are separated by a thin film of oil, the friction and heat are reduced.

兩個金屬面相擦，就要產(chǎn)生摩擦和熱;但如果在它們之間抹上薄薄的一層油，就可以減少摩擦，降低熱度。

No machine would work for long if it were not properly lubricated.

任何機械如果不使用一定的潤滑劑，就不能持續(xù)工作。

The oil used for this purpose must be of the correct thickness; if it is too thin it will not give sufficient lubrication, and if it is too thick it will not reach all parts that must be lubricated.

潤滑油的濃度必須適當，太稀則起不到應有的潤滑作用，太稠則流不到所有需要潤滑的零件。

責任編輯：admin