I'd like to go by climbing a birch tree, And climb black branches up a snow-white trunk toward heaven, till the tree could bear no more, But dipped its top and set me down again.

我真想去爬白桦树，沿着雪白的树干，爬上乌黑的树枝，爬向那天心，直到树身再支撑不住，树梢碰着地，把我放下来。

耶鲁公开课 - 现代诗歌课程节选

The point I wanted to make is that for every node, except the leaves, the leaves are the bottom of a tree in this case, are weird, right, they draw trees where the root is at the top, and the leaves are at the bottom.

你没必要看到整棵树，我想说的重点是,对每个节点来说，除了叶子节点,叶子节点指的是树的最下面的节点，电脑科学家都很奇怪,他们画树的时候根是在最上面的。

麻省理工公开课 - 计算机科学及编程导论课程节选