The ai is substituted for e forming part of the affixes of the first person of the loṭ (Imperative Mood).,
This relates to the Atmanepada affix. Thus करवै, करवावहै, करवामहै ।
But the ए resulting from sandhi, is not to be changed into ऐ । Thus पचाव + इदम् = पचावेदम्, पचाम + इदम् = पचामेदम् । Here, no doubt, the ए belongs to the Imperative by 6.1.85, being the substitute of अ of म and व. But this is not to be changed into ऐ on the maxim that this ए is the result of a बहिरङ्ग rule, for the rule of sandhi 6.1.87, is a बहिरङ्ग rule, while the present sutra is an अन्तरङ्ग rule; because of the following Paribhasha, असिद्धं बहिरङ्गमन्तरङ्गे 'that which is Bahiranga is regarded as not having taken effect, when an Antaranga rule is to be applied.,