indicating period or circumstance in which something happened or is happening: during, in, under · indicating movement to the other side of something: behind, beyond, over · indicating taking a standing or seated position next to something: at, to
köken: From suffixed noun ért, éret (“instead of sth., in exchange”), evolved from *ér (“presumably "place"”), a noun of unknown origin extended with -t (“locative suffix”).
in the direction of, to, towards · on account of, according to, because of, due to, for (the purpose of) · against; facing
köken: From Proto-Italic *op, from Proto-Indo-European *h₁epi. Cognate with Ancient Greek ἐπί (epí), Sanskrit अपि (ápi), Avestan 𐬀𐬌𐬞𐬌 (aⁱpi), Old Persian [script needed] (apiy), and Old Armenian եւ (ew). Also related to English by. The accusative is from the pre-PIE directional and the PIE direct object.
used to indicate the place someone or something is going to or toward; for, to · used to indicate an amount of time; for, in, during · used to indicate the time when something is arranged or intended to happen; for