单项选择题
The connecting rod is fitted between the crosshead and the crankshaftI t transmits the firing force, and together with the crankshaft converts the （）motion to a （）motion.
A.rotary；reciprocating B.up and down；fore and aft C.fore and aft；up and down D.up and down；rotary
单项选择题 The intake ports of a two-strike/cycle diesel engine are opened and closed by the action of the （）
单项选择题 Valves in the cylinder head of a diesel engine are opened by the direct action of the（）
单项选择题 On a large diesel engine installation, crankshaft axial alignment is maintained by the （）
