sand box cover

例句：

1. 1. The sandbox cover is made of sturdy plastic material.
   沙箱盖是由坚固的塑料材料制成的。
2. 2. The children were playing in the sandbox when the rain started.
   当雨开始时，孩子们正在沙箱里玩耍。
3. 3. The sandbox cover protects the sand from getting wet.
   沙箱盖保护沙子不受湿气影响。