Declension table of ?tejastva

Neuter	Singular	Dual	Plural
Nominative	tejastvam	tejastve	tejastvāni
Vocative	tejastva	tejastve	tejastvāni
Accusative	tejastvam	tejastve	tejastvāni
Instrumental	tejastvena	tejastvābhyām	tejastvaiḥ
Dative	tejastvāya	tejastvābhyām	tejastvebhyaḥ
Ablative	tejastvāt	tejastvābhyām	tejastvebhyaḥ
Genitive	tejastvasya	tejastvayoḥ	tejastvānām
Locative	tejastve	tejastvayoḥ	tejastveṣu

Compound tejastva -

Adverb -tejastvam -tejastvāt