"Kēhau is a student."
Translation:He haumāna ʻo Kēhau.
He haumāna ʻo Kēhau, but He mākaʻi i au. Why in one sentence ʻo, but the other i for the word 'is'.
I can't explain the i in that second sentence (I would have written it without, but I'm just a student). However, the ‘o in the sentence from this exercise is just a third person marker. It is required in front of ia and names, but has no translatable meaning. It is NOT a verb like "is"! However, since au is not ia and not a name it does not get ‘o in front of it.