underground portion

• 地下部分

underground portion的用法和样例：

例句

1. The roots are the underground parts of the tree that supply it with nourishment.
   树根是树的地下部分，用于供应养分。
2. Effect of laser process Chinese pine on the seedling growth of both aerial and underground part is studied.
   研究了用激光处理油松种子对其幼苗地上部分和地下部分的影响。