trunk of a tree

例句：

1. 1. The tree's trunk is thick and sturdy.
   这棵树的树干又粗又结实。
2. 2. Thetrunk of the tree was badly damaged bythe storm.
   这棵树的主干被暴风雨严重损坏了。
3. 3. The trunk of the treeis where the roots grow.
   这棵树的主干是根生长的地方。