(jeden) Fridrich; (bez) Fridricha; (k) Fridrichovi; (vidím) Fridricha; (hej) Fridrich!; (o) Fridrichovi; (s) Fridrichom;
(dvaja) Fridrichovia; (bez) Fridrichov; (k) Fridrichom; (vidím) Fridrichov; (hej) Fridrichovia!; (o) Fridrichoch; (s) Fridrichmi;