Pāṇini sūtras

The sa of the Particle su is changed to ṣa in the Chhandas, when preceded by another word having in it the change-effecting letter i &c.

German Im Veda geht auch das s der Partikel su in ṣ über. (107)

1. suñaḥसुञः

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   sस्	suñसुञ्	suñaḥसुञः	suसु	suñसुञ् + plus aḥअः

Anuvṛtti

1. a+pada+antasyaअ+पद+अन्तस्य 8·3·55

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   aअ	aअ	aअ	not	aअ
   pप्	padaपद	padaपद	word	padपद् + plus aअ
   aअ	antaअन्त	antasyaअन्तस्य	last syllable	antअन्त् + plus asyaअस्य

2. i+ṇ+koḥइ+ण्+कोः 8·3·57

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   iइ	iइ	iइ	ikāraइकार	iइ
   ṇण्	ṇण्	ṇण्	NaNअ	ṇण्
   kक्	kuकु	koḥकोः	guttural	kक् + plus oḥओः

3. chandasiछन्दसि 8·3·105

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   cच्	chandasछन्दस्	chandasiछन्दसि	Veda	chandछन्द् + plus asiअसि

4. pūrva+padātपूर्व+पदात् 8·3·106

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   pप्	pūrvaपूर्व	pūrvaपूर्व	antecedent	pūrvaपूर्व
   pप्	padaपद	padātपदात्	word	padपद् + plus ātआत्

5. saḥसः 8·3·56

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   sस्	sस्	saḥसः	sakāraसकार	sस् + plus aḥअः