单项选择题
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
单项选择题 The fuel pipes and ducts should be blown with （）.
单项选择题 The fuel oil system for a diesel engine can be considered in two parts--the fuel supply and the （） systems.
单项选择题 The fuel is supplied to the pump through ports or openings in the （） or cylinder of the pump.
