问题：
[单选] The withdrawing of the cylinder liners, in general, depends on their （）.This may amount to approximately 1/120 of the diameter in some engines.
correct maneuvering。wear。working efficiency。maintenance。
问题：
[单选] The words such as quantity, grade, viscosity and specific gravity should be in the （）.
repair list。spare parts order list。price list。bunker list。
问题：
[单选] The work fuel does in each working cycle can be obtained by taking the （）.
precautions。rpm。indicator cards。B and C。
问题：
[单选] The working cycle of a four-stroke diesel engine consists of four events:（） (1) compression (2) expansion (3) exhaust (4) suctionThe correct sequence is
(4)-(2)-(3)-(1)。(4)-(3)-(1)-(2)。(4)-(3)-(2)-(1)。(4)-(1)-(2)-(3)。
问题：
[单选] There is （） in any water cooling system for a diesel engine allowing for expansion and water make-up in the system as well as air vent and chemicals addition.
a setting tank。a service tank。a head tank。an expansion joint。
问题：
[单选] There is an injection pump for each cylinder, which is usually operated once every cycle by （） on the camshaft.
a gear。a cam。a rod。a miler。
问题：
[单选] There should be a lubricating oil （） between the main beatings and the crankshaft.
film。cap。lacquer。shell。
问题：
[单选] These piston rings are so badly worn that they must be （）.
renewed。welded。machined。chromium-plated。
问题：
[单选] They understand the （） of automatic sludge discharging of the purifierBut they are not good in practice.
principle。principal。cause。case。
问题：
[单选] This used piston had been tested and approved as a spare part by the （） during last annual repair.
agent。shipchandler。surveyor。engineer。
