单项选择题
Fuel oil begins injection into the cylinder of a four-stroke/cycle diesel engine during the （）.
A.intake stroke B.exhaust stroke C.power stroke D.compression stroke
单项选择题 Telescopic pipes to the piston of a large slow-speed main propulsion diesel engine are designed to prevent （）.
单项选择题 The water in an auxiliary boiler should be tested daily for （）.
单项选择题 A feed pump for an auxiliary boiler might lose suction if the （）.
