A THING THAT HAS HAPPEN的用法和样例：
- What is the funniest thing that has happened at the lan?
- You have cause me to lose my temper: a thing that have hardly ever happen to me.
- A superlative adjective that identifies a thing that has a quality above or below the level of at least two others.
- To receive a bite was the worst thing that has happened to me since I came to England.
- A person or thing that has no equal; a paragon.