One person, several name forms

An official name is used in documents and many formal settings: for example, Катерина. In everyday conversation, the same person may introduce herself as Катя. Family or close friends may use an affectionate form such as Катруся.

The forms are connected, but they are not interchangeable commands on a grammar chart. Two people with the same official name may prefer different everyday forms, and some people prefer only their full name.

A useful question is Як до вас звертатися?—“How should I address you?” You can also simply mirror the form a person uses when introducing themselves.

When you speak directly to someone, the name may also take a vocative form. That is a separate grammatical change covered in the companion card.