तद् अस्य तद् अस्मिन् स्याद् इति

The word तद् shows that the word in construction must be in the Ist case, the words अस्य 'of it' and अस्मिन् 'in it' show the senses of the affix, the word स्यात् 'it can be' qualifies the primitive, the word इति is for the sake of distinctness. Thus प्राकार आसाम् इष्टकानां स्यात् = प्राकारीया इष्टकाः 'the bricks sufficient to raise a wall'. So also प्रासादीयं दारु ॥ Similarly प्राकारोऽस्मिन्देशे स्यात् = प्राकारीयो देशः 'a place sufficient to make a wall therein'. प्रासादीया भूमिः ॥

The word स्यात् being in the Potential Mood (विधि लिङ्) of अस् 'to be,' has the force of संभावन 'potentiality, sufficiency' as given in Sutras 3.3.154 &c. Such as when the large number of bricks makes it possible to raise a wall, we say प्राकार यासामिष्टकानां स्यात् ॥ Similarly when the quality (गुण) of a land, such as its area, situation &c, makes it possible to erect a palace therein, we say, प्रासादो स्मिन्देशे स्यात् ॥

In the examples under this sutra, there is no modification (विकार) of the primitive (प्रकृति) into a product, as was the case under sutra 5.1.12. The examples under this sutra show merely the 'adequacy, fitness or sufficiency' of a thing for a certain purpose. Herein lies the difference between this sutra and the previous ones.

The repetition of the word तद् twice in this sutra shows the existence of this Grammatical maxim: अनेकस्मिन् प्रत्ययार्थे प्रत्येकं समर्थ विभक्तिः संबन्धनीयः 'when the sense of an affix is more than one, the case in construction to which the affix must be added must be shown in each case.'

Why there is no affixing in this case: प्रासादो देवदत्तस्य स्यात् ? The use of इति in the Sutra would prevent this, the force of इति being that the secular usage must be looked to in forming these derivatives.,