The affixes sa and snau come after mṛd when it means 'excellence'.,
This debars the affix रूपप् 5.3.66. Thus प्रशस्ता मृद् = मृत्सा or मृत्स्ना ॥ These two affixes are nitya or invariable, i. e. whenever superiority is to be expressed we must add these affixes. The reason for our calling it nitya is that the word अन्यतरस्याम् 'optionally' follows it in 5.4.42, so that this affix is not optional c. 5.4.7, 5.4.10, &c.,