Unlike the light nūn, the heavy nūn is used in all 14 grammatical slots of the imperfect paradigm.
Its ending contains the mushaddad nūn نَّ. Some surface forms repeat, but each person/number/gender slot still counts separately. Read the row and column together rather than counting only distinct spellings.
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Emphasis in the Imperfect: Light and Heavy Nun
Unlike the light nūn, the heavy nūn is used in all 14 grammatical slots of the imperfect paradigm.
Its ending contains the mushaddad nūn نَّ. Some surface forms repeat, but each person/number/gender slot still counts separately. Read the row and column together rather than counting only distinct spellings.