stack of fuel elements

例句：

1. 1. The books are neatly stacked on the shelf.
   书整齐地堆放在书架上。
2. 2. He stacked the boxes in the corner of the room.
   他在房间的角落里堆放箱子。
3. 3. The mountain was covered with a thick layer of snow, making it difficult to stack the skis.
   山上覆盖着厚厚的雪层，使得滑雪板难以堆叠。