Declension table of ?dīrghaparvan

Masculine	Singular	Dual	Plural
Nominative	dīrghaparvā	dīrghaparvāṇau	dīrghaparvāṇaḥ
Vocative	dīrghaparvan	dīrghaparvāṇau	dīrghaparvāṇaḥ
Accusative	dīrghaparvāṇam	dīrghaparvāṇau	dīrghaparvaṇaḥ
Instrumental	dīrghaparvaṇā	dīrghaparvabhyām	dīrghaparvabhiḥ
Dative	dīrghaparvaṇe	dīrghaparvabhyām	dīrghaparvabhyaḥ
Ablative	dīrghaparvaṇaḥ	dīrghaparvabhyām	dīrghaparvabhyaḥ
Genitive	dīrghaparvaṇaḥ	dīrghaparvaṇoḥ	dīrghaparvaṇām
Locative	dīrghaparvaṇi	dīrghaparvaṇoḥ	dīrghaparvasu

Compound dīrghaparva -

Adverb -dīrghaparvam