"There is a period at the end of this sentence."
Translation:Estas punkto je la fino de tiu ĉi frazo.
It's more a question of why "je" is accepted. Since we are talking about a location for a symbol "ĉe" should be the correct proposition shouldn't it? (If the answer to that question is no, then we would, logically, be able to use "ĉe" for all locations.)
Does anyone know where the word "punkto" is derived from? I know "ponc" is used for the periods in internet addresses in Irish - but I haven't seen any other word in Esperanto that is derived from an Irish/Celtic word.
Do remember, though, that Zamenhoff was well versed in Latin, as well as German. It could be from both. In fact, if a root was common in several different languages, it was rather assured of becoming an Esperanto root.