"Other houses are good"
Translation:Nyumba nyingine ni nzuri
Ah, I didn't see that in the tips and notes. Yeah, personally, I like zingine and I think they should accept both.
Here are some articles about -ingine
Some people (including at least one president) do say zingine in class 10, but the prescribed standard form is nyingine as it is simply an adjective. Adjectives, like nouns, do not distinguish between classes 9 and 10.
There's a similar thing in class 5, where the standard form is jingine but some people use lingine instead, using the verbal rather than adjectival prefix.