If a word's final letter is 's' is replaced by 'ru'..this 'ru' is special 'r'
azvas -> azva + ru(this 'ru' is special 'r'
If the first words last letter is 'r' and next words first letter is khar letter 'r' replaced by 'H'..as well 'r' replaced by 'H' when pause(end of sentence)
with a normal r, before pause --
punar + pause -> punaH
with a ru made by sasaju, before pause --
azvas + pause
-> azva + ru + pause by sasaju
-> azvaH + pause by kharava
before khar letters, like kh --
punar + kharaH -> punaH kharaH "again mule"
azvas + kharaH -> azva + ru + kharaH -> azvaH kharaH "horse mule"