Ater said the "rule" prohibiting prepositions from ending a sentence is nonsense. I interpreted that as "It is perfectly acceptable to end a sentence with a preposition." I could not determine whether he referring to doing so in writing or in verbal communication. I assumed it was the former, hence why I responded in the form of two examples, attempting to explain that when writing, I tend to follow that "rule" and avoid ending sentences with prepositions wherever possible, because I feel as if I appear ignorant otherwise. I will admit, though, that the examples I composed could be a line of dialogue, in which case ending the sentence with "under" does not sound odd.