The affixes called kṛtya also come after a root when the sense to be indicated is that of 'necessity' or 'obligation'.,
Thus भवता खलु अवश्यं कटः कर्त्तव्यः, करणीयः, कार्यः or कृत्यः 'you ought to make the mat'; भवता शतं दातव्यं, देयं, &c, 'you ought to pay a hundred'.
Q.-- Where is the necessity of this aphorism ? The kritya affixes, being enjoined universally without any limitation would, of course, come under these special circumstances also.
A.-- They would be excluded by the special affix णिनि of the last sutra, which comes especially with the force of 'necessity' and 'obligation'.
Q.-- Not so, for णिनि comes in denoting the 'agent' (कर्ता), while kritya denotes the 'action' (भाव) and the 'object' (कर्म); so their scope being different, how can one supersede the other ?
A.-- Well, to remove this objection, some say, that kritya words like भव्य, गेय &c. 3.4.68 which especially refer to the agent, are the proper examples to be given under this aphorism; and not examples of kritya-formed words in general.,