Declension table of ?tvaṅkya

Neuter	Singular	Dual	Plural
Nominative	tvaṅkyam	tvaṅkye	tvaṅkyāni
Vocative	tvaṅkya	tvaṅkye	tvaṅkyāni
Accusative	tvaṅkyam	tvaṅkye	tvaṅkyāni
Instrumental	tvaṅkyena	tvaṅkyābhyām	tvaṅkyaiḥ
Dative	tvaṅkyāya	tvaṅkyābhyām	tvaṅkyebhyaḥ
Ablative	tvaṅkyāt	tvaṅkyābhyām	tvaṅkyebhyaḥ
Genitive	tvaṅkyasya	tvaṅkyayoḥ	tvaṅkyānām
Locative	tvaṅkye	tvaṅkyayoḥ	tvaṅkyeṣu

Compound tvaṅkya -

Adverb -tvaṅkyam -tvaṅkyāt