单项选择题
A.a reduction B.an increase C.an outing D.a downwards
A number of cylinder liners are enclosed in one cast ir...
单项选择题A number of cylinder liners are enclosed in one cast iron casing to form a （）.
A.cylinder cover B.cylinder block C.cylinder frame D.bed-plate
A main bearing consists of two shells which are secured...
单项选择题A main bearing consists of two shells which are secured by means of studs and （）.
A.tie rods B.through bolts C.lead wires D.bearing caps
A lubricant often has to perform many duties in any sit...
单项选择题A lubricant often has to perform many duties in any situation, in addition to its fundamental job of （）.
A.resisting oxidization B.reducing friction C.promoting moving speed D.developing inertia
