sheltering coefficient

例句：

1. 1.The storm made it difficult for us to find a safe shelter.
   暴风雨让我们难以找到一个安全的避难所。
2. 2.He hid in the shelter of the tree.
   他躲在树的掩护下。
3. 3.She found a safe shelter from the flood.
   她找到了一个安全的避难所，免受洪水侵袭。