Pāṇini sūtras

For the a or ā (not standing at the end of a Pada or full word) + u of us the Tense-affix, the second vowel is the single substitute.

German Auch für ein nicht am Ende eines Wortes stehendes (a oder) ā + u von us (d. i. vor der Personalendung us). (96)

1. usiउसि

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   uउ	usउस्	usiउसि	usउस्	usउस् + plus iइ

2. a+pada+antātअ+पद+अन्तात्

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

Anuvṛtti

1. saṃhitāyāmसंहितायाम् 6·1·72

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   sस्	saṃhitāसंहिता	saṃhitāyāmसंहितायाम्	continuous speech	saṃhitसंहित् + plus āyआय्

2. ya+ṇ+a+ciय+ण्+अ+चि 6·1·77

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   aअ	aअ	aअ	akāraअकार	aअ
   cच्	cच्	ciचि	CC	cच् + plus iइ

3. pūrva+parayoḥपूर्व+परयोः 6·1·84

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   pप्	pūrvaपूर्व	pūrvaपूर्व	antecedent	pūrvaपूर्व
   pप्	paraपर	parayoḥपरयोः	following	paraपर + plus yoḥयोः

4. ā+tआ+त् 6·1·87

   Part	Lexeme	Sandhi form	Meaning	Stem
   āआ	āआ	āआ	ākāraआकार	āआ
   tत्	tत्	tत्	TT	tत्

5. para+rūpamपर+रूपम् 6·1·94

   Part	Lexeme	Sandhi form	Meaning	Stem + termination
   pप्	paraपर	paraपर	following	paraपर
   rर्	rūpaरूप	rūpamरूपम्	vowel	rūpरूप् + plus amअम्