The original root letters of قَاتَلَ are ق، ت، ل.
The added Alif comes between the first root letter ق and the second root letter ت.
That gives the visible structure قَاتَلَ.
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Root and Structural Signature
Derived Trilateral (without Hamzah) - Bab 4: Mufaa'alah (Muqatalah)
The original root letters of قَاتَلَ are ق، ت، ل.
The added Alif comes between the first root letter ق and the second root letter ت.
That gives the visible structure قَاتَلَ.