1.bolster:support=tackle:hoist 工具及其作用关系 而axis:revolve(axis是轴线 轴的意思 revolve是旋转 只能理解为东西绕着轴线旋转 并不是作用的关系)
(tackle: an assemblage of ropes and pulleys arranged to gain mechanical advantage for hoisting and pulling)
(bolster: a structural part designed to eliminate friction or provide support or bearing)