树上有五只鸟用英语怎么说

there are five birds in the tree.
在树上 可用in the tree 指外去的。
而树上本身具有的要用 on the tree
eg：

There are five apples on the tree.
树上结5 个苹果。

There are five birds in the tree.
in the tree指在树上，并非长在树上，是树以外的东西。
on the tree指树上长的，例如：There are same apples on the tree.

There are five birds in the tree.

There are five birds in the tree.

Five birds are perching in the tree.