单项选择题
A.stop the engine by cutting off the cooling water supply
B.stop the engine by closing the air intake
C.slow the engine but not stop it
D.slow the engine to half of normal load
单项选择题 Oil control rings used in two-stroke/cycle diesel engines are located near the bottom of the piston skirt in order to （）
单项选择题 In describing basic diesel engine operation，the term ‘event’ refers to （）
单项选择题 To shut down a diesel engine after it exceeds the set maximum speed，which type of device listed should be used?（）