Declension table of ?kṛṣṇasūtra

Masculine	Singular	Dual	Plural
Nominative	kṛṣṇasūtraḥ	kṛṣṇasūtrau	kṛṣṇasūtrāḥ
Vocative	kṛṣṇasūtra	kṛṣṇasūtrau	kṛṣṇasūtrāḥ
Accusative	kṛṣṇasūtram	kṛṣṇasūtrau	kṛṣṇasūtrān
Instrumental	kṛṣṇasūtreṇa	kṛṣṇasūtrābhyām	kṛṣṇasūtraiḥ kṛṣṇasūtrebhiḥ
Dative	kṛṣṇasūtrāya	kṛṣṇasūtrābhyām	kṛṣṇasūtrebhyaḥ
Ablative	kṛṣṇasūtrāt	kṛṣṇasūtrābhyām	kṛṣṇasūtrebhyaḥ
Genitive	kṛṣṇasūtrasya	kṛṣṇasūtrayoḥ	kṛṣṇasūtrāṇām
Locative	kṛṣṇasūtre	kṛṣṇasūtrayoḥ	kṛṣṇasūtreṣu

Compound kṛṣṇasūtra -

Adverb -kṛṣṇasūtram -kṛṣṇasūtrāt