Earlier quoted context omitted.
It's not even just "indo-european" bias, it's just that word-for-word translation of sentences without any context only gets you so far. Even for something as "simple" as English-to-French it breaks down when the languages don't map 1:1 with each other. For instance there's no single way to translate "I ran" in French, it could be "j'ai courru" or "je courrais" depending on context and depending no the lesson Duoling…
Which is fine. It is about being understood. You are never going to get fluent from a course. Language changes, and even native speakers are learning new things.
And there are no hard rules. In that sentence you can't just put +I to make it definite as I described above "ayiyi cikabilir" "der". This is like Duolingo saying 'the'='der' and rejecting 'das' and 'die'.
So, it is not fine, it is wrong. And the wrong thing is not that Duolingo has a bug, it is that it has made-up grammar rules, which users still have to learn. If they never learned this rule, they'd be as well understood.
(I know you were replying to commenter discussing French, but I'm guessing something similar is going on)