جَاءَنِي زَيْدٌ جَعْفَرٌ — Zayd—rather, Jaʿfar—came to me.
جَاءَ: past verb.
نِي: attached object with protective nūn.
زَيْدٌ: initially uttered nominative subject and antecedent.
جَعْفَرٌ: nominative badal of correction; Jaʿfar is the intended visitor.
This is a constructed grammatical example, not a report about an actual event.