Kāna can contextually mean “became” while retaining the defective-verb case pattern. This is semantic, not a separate fourth inflectional class.
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Kāna in the Sense of Becoming
Defective Verbs: Kāna and Its Sisters
Kāna can contextually mean “became” while retaining the defective-verb case pattern. This is semantic, not a separate fourth inflectional class.