单项选择题
Vents are led from the engine to head tank （） from the cooling water.
A.for the release of air B.for the release of water C.in order to the release of air D.because the release of air
单项选择题 Vee-type engines have the connecting rods from two cylinders connected to each （） of the crankshaft.
单项选择题 Valve overlap is the period during which （）.
单项选择题 Valve gear knocks are more easily located while the engine （）.
