Here's why:
* Concrete "flight": When "flight" refers to the physical act of flying, it describes a specific action or movement. In this case, it's not abstract, as it refers to something tangible.
* Example: "The bird took flight."
* Abstract "flight": When "flight" refers to a more general concept or idea, like the act of escaping, soaring, or the journey itself, it becomes abstract. It's not something you can touch or see directly.
* Example: "The prisoner's flight to freedom was daring."
* Example: "The flight of fancy took her to distant lands."
So, whether "flight" is abstract or concrete depends on the context.