tasya .
'tasya' ('of that', genitive).
tasya iti tu vaktavyam .
But (tu) 'tasya' ('of that') should be stated [in the sūtra].
kim prayojanam .
What is the purpose?
yaḥ yasya tulyāsyaprayatnaḥ saḥ tasya savarṇasañjñaḥ yathā syāt .
So that whichever [sound] has equal place-and-effort with respect to which [other], that one may be savarṇa-designated with respect to that [other].
anyasya tulyāsyaprayatnaḥ anyasya savarṇasañjñaḥ mā bhūt .
Let it not be that [a sound] having equal place-and-effort with one [sound] is savarṇa-designated with respect to another [different one].
tasya avacanam vacanaprāmāṇyāt .
The non-statement of 'tasya' [is right], because of the authority of the [existing] statement (vacana-prāmāṇya).
tasya iti na vaktavyam .
'tasya' need not be stated.
anyasya tulyāsyaprayatnaḥ anyasya savarṇasañjñaḥ kasmāt na bhavati .
[Then] why does it not happen that [a sound] having equal place-and-effort with one is savarṇa-designated with respect to another?
vacanaprāmāṇyāt : savarṇasañjñāvacanasāmarthyāt .
Because of the authority of the statement (vacana-prāmāṇya): that is, because of the force (sāmarthya) of the statement of the savarṇa-designation.
yadi hi anyasya tulyāsyaprayatnaḥ saḥ anyasya savarṇasañjñaḥ syāt savarṇasañjñāvacanam anarthakam syāt .
For if [a sound] having equal place-and-effort with one were savarṇa-designated with respect to another, the statement of the savarṇa-designation would be purposeless.
sambandhiśabdaiḥ vā tulyam .
Or (vā), [it is] like (tulyam) the correlative words (sambandhi-śabda).
sambandhiśabdaiḥ vā punaḥ tulyam etat .
Or again (vā punaḥ), this is like the correlative words (sambandhi-śabda).
tat yathā sambandhiśabdāḥ : mātari vartitavyam , pitari śuśrūṣitavyam iti .
As for instance the correlative words: 'one should behave [rightly] toward the mother', 'one should serve the father' — thus.
na ca ucyate svasyām mātari svasmin vā pitari iti sambandhāt ca etat gamyate yā yasya mātā yaḥ ca yasya pitā iti .
And it is not said 'toward one's own mother' or 'toward one's own father'; yet from the relation itself this is understood: 'who is whose mother, and who is whose father'.
evam iha api tulyāsyaprayatnam savarṇam iti atra sambandiśabdau etau .
So here too, in 'that which has equal place-and-effort is savarṇa', these two [tulyāsyaprayatna and savarṇa] are correlative words (sambandhi-śabda).
tatra sambandhāt etat gantavyam : yat prati yat tulyāsyaprayatnam tat prati tat savarṇasañjñam bhavati iti .
There, from the relation this is to be understood: 'with respect to which [sound] a [sound] has equal place-and-effort, with respect to that it becomes savarṇa-designated' — thus.