The five indicative patterns have an ending nūn:
يَرْمِيَانِ — تَرْمِيَانِ — يَرْمُونَ — تَرْمُونَ — تَرْمِينَ
Translation: the two throw; you two throw; they men throw; you men throw; you (fem.) throw.
Their final nūn marks the indicative in these forms. With لَنْ or لَمْ, that nūn is removed. This is not the same morphological event as the deletion of a final weak letter in singular jussive forms.
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The Five Indicative Forms
Full Conjugation of the Yāʾ-Final Verb رَمَى يَرْمِي
The five indicative patterns have an ending nūn:
يَرْمِيَانِ — تَرْمِيَانِ — يَرْمُونَ — تَرْمُونَ — تَرْمِينَ
Translation: the two throw; you two throw; they men throw; you men throw; you (fem.) throw.
Their final nūn marks the indicative in these forms. With لَنْ or لَمْ, that nūn is removed. This is not the same morphological event as the deletion of a final weak letter in singular jussive forms.