The Desiderative s may optionally take the iṭ augment after a root ending in iv and after 1. ṛdhu 2. bhrasja 3. dambhu 4. śri 5. svṛ 6. yu 7. ūrṇu 8. bhṛ 9. jñap and 10. san,
Thus दिदेविषति or दुद्यूषति, सिसेविषति, सुस्यूषति ॥ ऋध्, अर्द्दिधिषति, ईर्त्सति ॥ भ्रस्ज, बिभ्रज्जिषति, 6.4.47 बिभ्रक्षति, 8.2.36 and 8.2.41 बिभर्ज्जिषति, बिभर्क्षति ॥ दम्भु, दिदम्भिषति, धिप्सति, 7.4.56 धीप्सति, श्रि, उच्छिश्रयिषति, उच्छिश्रीषति ॥ स्वृ, सिस्वरिषति, सुस्वूर्षति ॥ यु, यियविषति, 7.4.80 युयूषति, ऊर्णु, प्रोर्णुनविषति, प्रोर्णुनुविषति, प्रोर्णुनूषति, ॥ The root भृञ् of the Bhuadi class is to be taken, as the form भर with शप् in the sutra indicates. बिभरिषति, बुभूर्षति,॥ ज्ञपि, जिज्ञपयिषति, ज्ञीप्सति ॥ सन्, सिसनिषति, सिषासति ॥ केचिदत्रभरज्ञपिसनितनिपतिदरिद्राणामिति पठन्ति, ॥ तितनिषति, तितंसति, तितांसति, पिपतिषति, पित्सति, दिदरिद्रिषति, दिदरिद्रासति ॥ सनीति किम्, देविता, भ्रष्टा ॥
Some add तन्, पत् and दरिद्रा also, as तितनिषति or तितंसति or तितांसति, 6.4.17 पिपतिषति or पित्सति 7.4.54, 8.2.29, 7.4.58 दिदरिद्रिषति or दिदरिद्रासति ॥ Why do we say 'Desiderative'? Observe देविता, भ्रष्टा ॥ The form अर्दिधिषति is thus evolved. The Desiderative root is अर्धिस, the ऋ being gunated by 7.3.86 before सन् ॥ Now we reduplicate it, and the second syllable धिस् will be reduplicated by (VI. I. 2). and the रेफ is not duplicated by (VI. I. 3): so we get धिस् to reduplicate, and ध is changed to द ॥ The form ईर्त्सति is thus evolved. By 7.4.55, the ऋ is changed to long ई, which is followed by र् by 1.1.57. Thus we have ईर्ध्स् as root, and ध्स is reduplicated, and the reduplicate is elided 7.4.58. The forms धिप्सति and धीप्सति are similarly formed.,