很多短语的字面意思和实际意思看似不相干，其实都有它的

His first novel was a flash in the pan, and he hasn't written anything decent since. 他的第一部小说如昙花一现，此后他再没写出像样的东西。

The trendy rock group was only a flash in the pan. 这个新潮摇滚乐队只是昙花一现。