In the singular feminine Haadhir position, the subject Yaa is dropped before Heavy Noon.
The preceding letter carries Kasrah as an indicator of the deleted Yaa.
Example:
تَفْعَلِينَ
becomes
لَتَفْعَلِنَّ
Recognition clue: Kasrah before Heavy Noon points to this one position.
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One Singular Feminine Haadhir Form: Yaa Drops
Structural Rules of Heavy and Light Noon-e-Ta'keed
In the singular feminine Haadhir position, the subject Yaa is dropped before Heavy Noon.
The preceding letter carries Kasrah as an indicator of the deleted Yaa.
Example:
تَفْعَلِينَ
becomes
لَتَفْعَلِنَّ
Recognition clue: Kasrah before Heavy Noon points to this one position.