堆叠

例句：

1. 1. The boxes are stacked neatly on the shelves.
   盒子整齐地堆放在架子上。
2. 2. The books are piled high in the corner of the room.
   书堆在房间角落很高。
3. 3. The snow is heaped up against the fence.
   雪堆在篱笆旁。