We have, I think, five prepositions that take or may take the prepositional case: в, на, о, при, по. But which of these (appart from в and на) take the locative in -ý when that form exists? And which don't?
При can also govern the locative form, especially in poetic language, though this usage is quite archaic.
Верстах в двух от него, возле неглубокого яра, при шляху, Григорий спешил казаков, расположил в ярке.
Ой, при лужку, при лужке…
Note the mix of the two cases in the song lyric above.
Also note that the form in -у is used both in locative and prepositional for some nouns (мост, полк, бок etc.)
Prepositional has quite a limited use with по and can be replaced with dative in most cases.
1Okay. Thank you. So при generally takes the prepositional, while the locative is archaic. And o and по never take the locative. Correct?– GergesFeb 14, 2016 at 16:17
По barely ever takes the prepositonal either. Hemingway's "For Whom the Bell Tolls" is По ком звонит колокол, but the answer in plural second would rather be по вам, not по вас in the modern language, though the latter is still acceptable. Otherwise you're correct.– Quassnoi ♦Feb 14, 2016 at 17:13
В мосте нет пользы - prepositional, no у– AnixxJun 30, 2022 at 19:04