Declension table of ?kaṣṭāyitavya

Masculine	Singular	Dual	Plural
Nominative	kaṣṭāyitavyaḥ	kaṣṭāyitavyau	kaṣṭāyitavyāḥ
Vocative	kaṣṭāyitavya	kaṣṭāyitavyau	kaṣṭāyitavyāḥ
Accusative	kaṣṭāyitavyam	kaṣṭāyitavyau	kaṣṭāyitavyān
Instrumental	kaṣṭāyitavyena	kaṣṭāyitavyābhyām	kaṣṭāyitavyaiḥ kaṣṭāyitavyebhiḥ
Dative	kaṣṭāyitavyāya	kaṣṭāyitavyābhyām	kaṣṭāyitavyebhyaḥ
Ablative	kaṣṭāyitavyāt	kaṣṭāyitavyābhyām	kaṣṭāyitavyebhyaḥ
Genitive	kaṣṭāyitavyasya	kaṣṭāyitavyayoḥ	kaṣṭāyitavyānām
Locative	kaṣṭāyitavye	kaṣṭāyitavyayoḥ	kaṣṭāyitavyeṣu

Compound kaṣṭāyitavya -

Adverb -kaṣṭāyitavyam -kaṣṭāyitavyāt