Declension table of sumantra

Neuter	Singular	Dual	Plural
Nominative	sumantram	sumantre	sumantrāṇi
Vocative	sumantra	sumantre	sumantrāṇi
Accusative	sumantram	sumantre	sumantrāṇi
Instrumental	sumantreṇa	sumantrābhyām	sumantraiḥ
Dative	sumantrāya	sumantrābhyām	sumantrebhyaḥ
Ablative	sumantrāt	sumantrābhyām	sumantrebhyaḥ
Genitive	sumantrasya	sumantrayoḥ	sumantrāṇām
Locative	sumantre	sumantrayoḥ	sumantreṣu

Compound sumantra -

Adverb -sumantram -sumantrāt