This is the 150th most frequent Croatian word.
ste
"Ste" is the Croatian plural form of "are," used as the second person plural of "to be."
In this sentence, "ste" is the second-person plural form of the verb "to be" used in a formal or polite context.
Vi ste učitelj.
You are a teacher.
Here, "ste" is used as the auxiliary verb in a question in the perfect tense to maintain politeness.
Da li ste već kupili kartu za predstavu?
Have you already bought a ticket for the show?
In this case, "Jeste" includes "ste" as part of a polite affirmative inquiry in the perfect tense.