请高手列出it happen that的用法 以及例句``谢谢

问题描述:

请高手列出it happen that的用法 以及例句``谢谢
我问的是it happen that
和to连什么用;;;

It happened that I met my teacher on my way home
我在回家路上碰巧遇上我的老师.
It happened that she bumped into a tree.
她碰巧撞上了一棵树.