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單項選擇題

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

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單項選擇題

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

單項選擇題

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