The augment num is added after the vowel of the roots masj and naś before an affix beginning with any consonant other than a semi-vowel or a nasal.,
As मङ्क्ता, मस्ज् + तृच् (no इट् by 7.2.10), add न् = मस् न् ज् + तृ, elide स् by 8.2.29, change ज् to क्, and न् to anusvara, which then becomes ङ् ॥ मङ्क्तुम्, मङ्क्तव्यम्, मंष्टा, मंष्टुम् and मंष्टव्यम् ॥ But मज्जनम् and नशिता, and मग्न 6.4.32. In मग्नः and मग्नवान्, the नुम् is supposed to be placed the last consonant in मस्ज्, in order that it may get elided.,