单项选择题
A.steam rather than gas is used to turn a shaft B.vapor rather than gas is used to turn a shaft C.the former uses gas to turn a shaft D.the latter uses gas to turn a shaft
The reason why more and more of the large merchant vess...
单项选择题The reason why more and more of the large merchant vessels are being powered by medium-speed diesel engines is （）.
A.they operate between 150 and 450 rpm B.they are connected to the propeller by gearing C.their smaller size and weight D.they can be connected directly to the propeller without gearing
The diesel engine is similar to the gasoline engine in ...
单项选择题The diesel engine is similar to the gasoline engine in that （）.
A.both of them are ignited by compressed air B.both of them are the forms of external combustion engines C.both of them have spark plugs D.the power is developed by the piston in the cylinder
Most troubles likely to occur with marine diesel engine...
单项选择题Most troubles likely to occur with marine diesel engine can, if located in time, be remedied with no difficulty and many can be （）if the engine is maintained with a high sense of responsibility to the people on the part of the motormen and engineers.
A.found out B.eliminated C.avoided D.lowered
