Category: "U"

У (location)

by Don  

The Russians also use the preposition у to mean “at” in the sense of “at someone's home/place.” In this sense it is similar to chez in French.

— Где ты был?
— У Тани.
“Where were you?”
“At Tanya's place.”
Завтра мы будем ужинать у Ивановых. Tomorrow we are having dinner at the Ivanovs.
Давай заниматься завтра вечером у тебя. Let's study at your place tomorrow evening.

Actually the meaning of у is a bit broader. It can also mean a person's office or workplace:

— Где ты была?
— У декана.
“Where were you?”
“At the dean's office.”
Мы провели всё утро у врача. We spent the entire morning at the doctor's office.