The question asks for the part of speech (udu okwu) of n'ulo (in the house). This word is formed from the preposition na/n' (in/at) combined with the noun ulo (house).
In Igbo grammar, when a preposition (n'/na) combines with a noun to indicate location, time, or manner, the resulting expression functions as an adverbial phrase. It modifies the verb by telling WHERE an action takes place. In Igbo grammatical terminology, such a word is classified as mputa okwu - a word or phrase that describes or modifies the circumstances of an action (where, when, or how something happens).
N'ulo is not simply a noun (aha) because the prepositional element changes its grammatical role. It is not a verb (vob). And while ntụala may refer to another grammatical category, mputa okwu is the correct classification for this type of locative expression in Igbo grammar.
