top water level in front of bridge

例句：

1. 1.The top of the mountain is covered insnow.
   山顶覆盖着雪。
2. 2. Thetop layer of soil isrich in nutrients.
   土壤的最上层富含养分。
3. 3. The top of the treeis covered in leaves.
   树的顶端长满了叶子。