Musnad ilayh is what the statement is about (Zayd); musnad is what is said about it (standing).
The khabar of mā/lā is the predicate following the negative governing particle.
«مَا زَيْدٌ قَائِمًا» denies Zayd’s being upright; it does not deny that Zayd exists.
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Predicate and Subject of Predication
The Predicate of Mā and Lā Resembling Laysa
Musnad ilayh is what the statement is about (Zayd); musnad is what is said about it (standing).
The khabar of mā/lā is the predicate following the negative governing particle.
«مَا زَيْدٌ قَائِمًا» denies Zayd’s being upright; it does not deny that Zayd exists.