单项选择题
The diesel engine must be started before it can run by it self For this purpose （） has to be used.
A.a starting system B.the starting air C.a starting operation D.A, B and C
单项选择题 The diesel engine is a type of internal combustion engine which ignites the fuel by injecting it into hot, high pressure air in a （）.
单项选择题 The diesel engine is a type of （）.
单项选择题 The diameters of the crankpins should be measured using （）.
