单项选择题
A.the bearing
B.the crosshead
C.bosses
D.bridges
单项选择题 The governor of a generator engine is to ().
单项选择题 The gas loads on the engine structure are constrained by means of hydraulically preloaded () which connect the bed plate, frame sections and cylinder jackets into a single unit.
单项选择题 The function of a lubricating oil is () to lubricate the running surface () to carry away a great deal of heat.