Questions & Answers about U kupatilu su peškir i sapun.
Because u can take different cases depending on the meaning:
- u + accusative = movement into something
- u + locative = being in something
In this sentence, the meaning is location, not motion, so Serbian uses the locative:
- kupatilo = bathroom
- u kupatilu = in the bathroom
Compare:
- Idem u kupatilo. = I am going into the bathroom.
- Ja sam u kupatilu. = I am in the bathroom.
Because together they form a compound subject: peškir i sapun = the towel and the soap.
Even though each noun is singular on its own, the whole subject is plural, so the verb must also be plural:
- peškir je = the towel is
- sapun je = the soap is
- peškir i sapun su = the towel and the soap are
So su is correct because there are two things.