a precious fool的用法和样例：
- I shall feel like a precious fool.
- A wager of twenty thousand pounds lost, because he, like a precious fool, had gone into that abominable pagoda!
- A precious lot of good that will do!
- Such a precious gift did he give me that I was deeply touched.
- Dorothea seized this as a precious permission.
- Iron is a base metal, gold a precious one.