trunk stem

• 主干

trunk stem的用法和样例：

例句

1. The main stem of a tree is a tapering geometricsolid.
   树木的主干是一种有消度的几何体。
2. The common trunk and lateral enous plexuses are coered and concealed by the prostatic and endopelic fascia.
   主干和侧支静脉丛被前列腺和盆内筋膜所覆盖。