The first thing about this sentence is that it was deleted because it lacked any context and also the accent on 'trio' is wrong, however the Duolingo system bug means that it is still lingering on for some people.

Secondly, your suggestion is almost correct, it should be 'Medra i drio', the 'yn' or the 'n' is only used in sentences with forms of 'bod' the verb to be.