There is a little bird in the tree.There are many pears on the tree.都是在树上为什么一个用in一个用on?
问题描述：
There is a little bird in the tree.There are many pears on the tree.都是在树上为什么一个用in一个用on?
答
in the tree 和on the tree 都是在树上
in the tree 是不是树上结的东西 There is a little bird in the tree.
on the tree 是树上结的 There are many pears on the tree.
总结：外来物用in,果实、叶子用on.