The reconstructed passive imperfect is يُقْوَلُ. Its fatḥah transfers from the weak radical to the preceding qāf; the wāw then changes to alif after fatḥah, yielding the actual form يُقَالُ.
يَقُولُ — he says.
يُقَالُ — it is said.
The retained wāw of the active and the alif of the passive reflect different phonological rules applied to one underlying root, not different lexical roots.
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Deriving the Passive Imperfect Yuqālu
Complete Conjugation of the Hollow Wāw Verb: Qāla–Yaqūlu
The reconstructed passive imperfect is يُقْوَلُ. Its fatḥah transfers from the weak radical to the preceding qāf; the wāw then changes to alif after fatḥah, yielding the actual form يُقَالُ.
يَقُولُ — he says.
يُقَالُ — it is said.
The retained wāw of the active and the alif of the passive reflect different phonological rules applied to one underlying root, not different lexical roots.