单项选择题 On opposite ends of a single shaft of a turboblower are a gas driven （）and a air compressor, which are sealed each other.

单项选择题 On a four-stroke diesel engine, when the piston is driven downwards by the expanding gas, it delivers power to the crankshaft through the （）.

单项选择题 On a diesel engine, fuel is delivered into the combustion space by （）.