Declension table of ?sāntvya

Neuter	Singular	Dual	Plural
Nominative	sāntvyam	sāntvye	sāntvyāni
Vocative	sāntvya	sāntvye	sāntvyāni
Accusative	sāntvyam	sāntvye	sāntvyāni
Instrumental	sāntvyena	sāntvyābhyām	sāntvyaiḥ
Dative	sāntvyāya	sāntvyābhyām	sāntvyebhyaḥ
Ablative	sāntvyāt	sāntvyābhyām	sāntvyebhyaḥ
Genitive	sāntvyasya	sāntvyayoḥ	sāntvyānām
Locative	sāntvye	sāntvyayoḥ	sāntvyeṣu

Compound sāntvya -

Adverb -sāntvyam -sāntvyāt