In the mantra literature, ktin acutely accented comes after the following roots, forming words in feminine gender, denoting a 'mere action' 1. vṛṣ 'to rain' 2. iṣ 'to wish 3. pac 'to cook' 4. man 'to think' 5. vid 'to know' 6. bhū 'to be' 7. vi 'to go, to consume' 8. rā 'to give'.,
The construction of this sutra is anomalous. Instead of the bases being put in the ablative case, they are put in the nominative case. Thus वृष्टिः 'raining'; इष्टिः 'wishing'; पक्तिः 'cooking'; मतिः 'thinking'; वित्तिः 'knowing'; भूतिः 'being'; वीतिः 'consuming'; रातिः 'giving'.
The affix क्तिन् has been generally ordained by sutra 94 after all verbs. The present sutra is made for the sake of regulating the accent in the case of these nouns. From इष् we have also an irregular noun इच्छा (III 3. 101), and another by the general rule 94 having acute accent on the first syllable, altogether 3 forms. See Rig Veda I. II6. 12; II 5. 6; 1.62. 3, 57. 2; IV. 24. 7; III. 39. I; I. 6. 5, 60. I; X. 95. 17 for these words.,