كَانَ زَيْدٌ هُوَ أَفْضَلَ مِنْ عَمْرٍو.
Kāna is a defective past verb; Zayd is its nominative noun; huwa is the separating form; afḍala is the accusative predicate of kāna; min ʿAmrin supplies the comparison.
The predicate stays accusative because of kāna; the intervening pronoun does not change its governing case.
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Pronouns: definitions, forms, usage, and parsing
كَانَ زَيْدٌ هُوَ أَفْضَلَ مِنْ عَمْرٍو.
Kāna is a defective past verb; Zayd is its nominative noun; huwa is the separating form; afḍala is the accusative predicate of kāna; min ʿAmrin supplies the comparison.
The predicate stays accusative because of kāna; the intervening pronoun does not change its governing case.