زَيْدٌ قَامَ
Zayd stood.
«Zayd» is a nominative mubtadaʾ. «Qāma» is a past-tense verb with a concealed subject pronoun «huwa» referring to Zayd. Together, the verb and its subject form a verbal clause serving as the predicate (khabar) of the outer subject.
«Qāma Zaydun», by contrast, starts with a verb followed by its explicit grammatical subject. It may convey the same event, but its grammatical packaging is not identical.