单项选择题
When a crankshaft （） outside the engine, it should be carefully supported in a manner which will avoid imposing high bending moments on it.
A.has to be handled B.may be handled C.has being handled D.will be handling
单项选择题 Vents are led from the engine to the head tank for the release of （） from the cooling water.
单项选择题 Vents are led from the engine to head tank （） from the cooling water.
单项选择题 Vee-type engines have the connecting rods from two cylinders connected to each （） of the crankshaft.
