滾入
The little pieces of which are broken off from hills and mountains roll down into the valleys,and we sometimes find great heaps of rough,sharp stones near the bottom of a mountain. 從巖石上剝落下來的小石頭片滾入山谷，我們有時在山腳的附近發(fā)現(xiàn)大量粗糙尖銳的石頭。
