The nominative indicates the subject of a sentence.
Example:
Er (N) wohnt hier. (He lives here.)
Seine Kinder (N) besuchen ihn oft (His
children visit him often.)
The nominative is also used for predicate nouns. A predicate
noun is a noun with which the subject is equated. Typically, the
verbs sein (to be), heißen (to be
called), and werden (to become) are used in
sentences that have a subject and a predicate noun. Example
sentences:
Sie ist Studentin. (She is a student.)
Sie heißt Nina. (Her name is Nina.)
Sie wird Ärztin. (She is becoming a physician. /
She will be a doctor / She is going to be a doctor)