ay is substituted for the i of ṇi before the affixes 1. ām 2. anta 3. ālu 4. āyya 5. itnu and 6. iṣṇu,
Thus कारयां चकार, हारयां चकार, गण्डयन्तः, मण्डयन्तः ( formed by the Unadi affix झच्, झ = अन्त, added to the roots गंड and मंड) आलु । स्पृहयालुः । आय्य, स्पृहयाय्यः, गृहयाय्यः ॥ इत्नुः - स्तनायत्नुः ॥ इष्णुः - पोषयिष्णुः ॥ Thus sutra could have been well dispensed with; for the इ of णि would take guna ए which will be changed to अय् by the rules of Sandhi, before these affixes. This substitution of अय् for इ is for the sake of the subsequent sutra however, because there इ could not be changed to अय by any sandhi-rules.,