sto

Sto, stare, steti, statum is first conjugation in the present but keeps an old reduplicated perfect, steti, never the regular stavi. That is the one irregular thing about it, and the compounds shorten it further: consto gives constiti, praesto gives praestiti, exsto gives exstiti.

Beyond standing on your feet it means to stand firm, to hold, and to cost. Stat sententia is "the decision stands"; multo sanguine stetit is "it cost much blood", with the price in the ablative. Do not confuse the perfect steti with that of sisto, "to set up", which is stiti and looks close enough to catch you out. Family: statio, statua, status, statuo, instans, circumsto. English stand is a Germanic cousin rather than a borrowing, but state, station, statue, stable, constant, instant and substance all come from this root, and Spanish estar is sto itself.