I did go and meet my friend last night. As a result, I didn’t get enough sleep, which always makes my bursitis flare up. Of course this would be the morning some punk kids chose my lawn on which to loiter, but I gave them what for. You may think I ended that sentence with a preposition, but in this case “what for” is an idiomatic expression disguising itself as a noun.

(Old person trifecta: complaint of physical ailment, derogatory reference to younger generation and a lesson.)