单项选择题
The main moving parts of a diesel engine consist of the （） and the pistons.
A.bedplate, connecting rods B.crankshaft, the connecting rods C.frames, crossheads D.crankshaft, the cylinder
单项选择题 The main function of the lubrication system in to enable （） of a film of oil between the moving parts.
单项选择题 The main factor which determines the output of each cylinder is （）
单项选择题 The main factor determining the output of each cylinder is the cylinder （）.
