In inna aṭ-ṭāliba yaktubu the verbal predicate fills a nominative slot; in kāna aṭ-ṭālibu yaktubu it fills an accusative slot. The verb itself stays indicative in both.
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Self-Test: Two Kinds of Predicate
Advanced Parsing Workshop: Integrated Grammar
In inna aṭ-ṭāliba yaktubu the verbal predicate fills a nominative slot; in kāna aṭ-ṭālibu yaktubu it fills an accusative slot. The verb itself stays indicative in both.