Declension table of mantavya

Masculine	Singular	Dual	Plural
Nominative	mantavyaḥ	mantavyau	mantavyāḥ
Vocative	mantavya	mantavyau	mantavyāḥ
Accusative	mantavyam	mantavyau	mantavyān
Instrumental	mantavyena	mantavyābhyām	mantavyaiḥ mantavyebhiḥ
Dative	mantavyāya	mantavyābhyām	mantavyebhyaḥ
Ablative	mantavyāt	mantavyābhyām	mantavyebhyaḥ
Genitive	mantavyasya	mantavyayoḥ	mantavyānām
Locative	mantavye	mantavyayoḥ	mantavyeṣu

Compound mantavya -

Adverb -mantavyam -mantavyāt