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單項選擇題

The function of a lubricating oil is （） to lubricate the running surface （） to carry away a great deal of heat.

A.not；but
B.neither；nor
C.either；or
D.not only；but also

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單項選擇題

The fuel pipes and ducts should be blown with （）.

A.atmosphere
B.the fresh water
C.compressed air
D.chemical compounds

單項選擇題

The fuel oil system for a diesel engine can be considered in two parts--the fuel supply and the （） systems.

A.fuel treatment
B.fuel combustion
C.fuel injection
D.fuel separating