Pāṇini sūtras

A word ending with the 7th case-affix is compounded with words ending with a kṛitya-affix (a fut. pass. Participle) and the resulting compound is Tatpurusha, when ‘debt’ is implied.

1. kṛtyaiḥकृत्यैः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   kक्	kṛtyaकृत्य	kṛtyaiḥकृत्यैः	kṛtyaकृत्य	kṛtyकृत्य् + plus aiḥऐः

2. ṛṇeऋणे

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   ṛऋ	ṛṇaऋण	ṛṇeऋणे	debt	ṛṇऋण् + plus eए

Anuvṛtti

1. saptamīसप्तमी 2·1·40

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   sस्	saptamaसप्तम	saptamīसप्तमी	seventh	saptamसप्तम् + plus īई