लिट्य् अभ्यासस्य+उभयेषाम्

Thus वच — उवाच, उवचिथ, स्वप् — सुष्वाप, सुष्वपिथ, यज — इयाज, इयजिय, टुवप् — उवाप्, उवपिथ ॥ As regards ग्रहादि verbs; ग्रह — जग्राह, जग्रहिथ (there is no speciality in case of this verb, as these forms would have been evolved without even this rule). ज्या — जिज्यौ, जिज्यथ, वयि — उवाय, and उवयिथ; व्यध — विव्याध, विव्यधिथ, वश — उवाश, उवशिथ, व्यच् — विव्याच, विव्यचिथ, व्रश्च — वव्रश्च and वव्रश्चिथ ॥ Some say that with regard to व्रश्च, it is equal whether there existed this present rule or not. For they argue thus, व्रश्च + णल् = व्रश् + व्रश्च् + अ = व + व्रश्च् + अ (हलादि शेषः 7.4.60) = वव्रश्च ॥ To this we reply, this form would be evolved no doubt had this rule not existed. But when this rule is applied, and you make reduplication without first vocalising the र, then you will have to vocalise व by force of this rule. Hence the necessity of this rule with regard to व्रश्च also, for having changed र into ॠ, we have वृव्रश्च् and then change ॠ into अ by 7.4.66. Then this अ substitute becomes sthanivat to ॠ 1.1.59, and therefore there is no vocalisation of this व, for rule 6.1.37, prevents the vocalisation of a letter standing before one which has already been vocalised. There is no speciality with regards to प्रच्छ and भ्रस्ज verbs.

This vocalisation of the reduplicate is taught with regard to those affixes which are not कित् ॥ With regard to कित् affixes, the Rule 6.1.15 will apply. And as the rule of vocalisation is subsequent to that of reduplication in order, therefore by the maxim of परत्व 1.4.2, vocalisation will take place first and then reduplication, according to the maxim पुनः प्रसङ्ग विज्ञानात्सिद्धम् \occasionally the formation of a particular form is accounted for by the fact that a preceding rule is allowed to apply again, after it had previously been superseded by a subsequent rule\. Thus वच् + अतुः (which is कित् 1.2.5) = उच् + अतुः = उच् + उच् + अतुः = ऊचतुः, ऊचुः ॥

Though the phrase उभयेषाम् could have been supplied into this sutra by the context and the governing scope of the preceding sutras, its express mention in this sutra is for the sake of indicating, that the rule of vocalisation supersedes even the rule of हलादिः शेषः 7.4.60, the vocalisation must take place at all events. Thus व्यध + णल् = व्य + व्यध + अ ॥ Here by 7.4.60, the second consonant य of व्य ought to have been elided, and the equation would have stood व + व्यध् + अ, and there would have been vocalisation of व by this rule. But that is not intended; there is vocalisation of य and we have विव्याध ॥ In fact, the universal maxim of vocalisation is :-\The samprasarana and the operations dependent on it possess greater force than other operations which are simultaneously applicable\. संप्रसारणं तदाश्रयं च कार्यम् बलवत् ॥,