lake sand

例句：

1. 1.The lake is covered in a layer of soft, white sand.
   湖面上覆盖着一层柔软的白色沙。
2. 2. The beach was littered with small pebbles and sand.
   海滩上散布着小石子和沙粒。
3. 3.The sand dunes were the perfect place to relax and enjoy the sun.
   沙丘是放松和享受阳光的理想之地。