 There are five noun classes in the singular, but only a distinction between "human" and "non-human" in the plural, the "male human" and "female human" having merged into "human", and the remaining classes into "non-human".The noun classes are visible through agreement in adjectives, adverbs, postpositions and demonstrative pronouns, and also verbs if the verb begins with a vowel.There are, however, some exceptions, like with irregular verbs in other languages.