The verb kulat is equivalent to English “to be”. It's the only irregular verb in Nûrlâm. It is used more rarely in Nûrlâm than in English for many reasons:

• For designation of state of being the verb “kul-” was required only in archaic language. Standard language described here and moreover colloquial speech do not use it for present tense. So the sentences like “I am orc”, “Sky is blue” should be translated in Nûrlâm as “I orc” (Izg uruk), “Sky blue” (Nût ulb). However it is still obligatory for past and future tenses.
• Agglutinative morphology of Black Speech do not require auxiliary verbs to express many grammatical forms.
• It's used much less with impersonal sentences.

However the verb “to be” is used in following constructions:

• Future non-perfect tenses as auxiliary verb.
• In past or future tense with predicative (dependent noun, adjective or participle).