The affixes ṇvul (ak) and tṛc (tṛ) are placed after all verbal roots, expressing the agent.,
The word 'root' is understood in the above aphorism. Thus कृ 'to do' + ण्वुल् = कार + यु (VII. 2. II5) = कार + अक (VII. I. I) = कारक nom. sing. कारकः 'doer.' कृ + तृच् = कर् + तृ 7.3.84 = कर्तृ nom. sing. कर्ता. So also हारकः and हर्ता.
The च् of तृच् is not indicatory, but distinguishes this affix from तृन्; the simple तृ includes both तृच् and तृन्, as in 5.3.59, and (VI. 4. I54).,