Now each year, more and more ice stacks up on top of it, and eventually it gets so heavy that it starts to slide down the mountain under its own weight, forming a slow-moving river of ice.
现在每年有越来越多的雪层层叠起 它变得非常重。 以至于由于它的重力作用 而滑下山。 形成缓慢移动的冰体。