deriv LSK ETT STT aSTA ALPH OLDHOMEPAGE NEWHOMEPAGE
For padafinal as अस् see sandhi of as before vowel.
For padafinal As आस् see sandhi of aas before vowel.
All the other padafinal s स् become r र् before vowels.
punar पुनर् + abravIt अब्रवीत् → punarabravIt पुनरब्रवीत् by no rules
gurus गुरुस् + abravIt अब्रवीत् → gururabravIt गुरुरब्रवीत् by sasajuSoruH