齿轮 gear [rack; toothed] wheel; (toothed) gear; wheel gear 伞齿轮 bevel gear; 斜齿轮 helical gear; 正齿轮 spur gear; 搭上齿轮 get [put; throw] into gear; 齿轮脱开 out of gear; 这个大齿轮带动小齿轮使滚筒旋转。 this large gear turns the small one to rotate the cylinder. 齿轮互相啮合。 the teeth of the wheel gear into each other