"Al-Azhar is an important Islamic university."
Translation:اَلْأَزْهَر جامِعة إِسْلامِيّة مُهِمّة.
Let me assume you mean Islamic instead of American. The farther an adjective is to the noun, and I mean that literally being written at the end of the sentence, the more likely will is be the main point of what you wanna say.
Think of it in English: Al-Azhar is an Islamic important university, or rather, Al-Azhar is an important university which is Islamic. (Emphasis that this important uni is Islamic) Al-Azhar is an important Islamic university. (Emphasis that this Islamic uni is important)
الازهر جامعة اسلامية مهمه That's exactly what I wrote as my answer. I know that I omitted most of the diacritics, but writing them on my phone's keyboard is a little too cumbersome.
Please, someone tell me what's wrong with my answer. Duolingo doesn't even explain it. My best guess is that at the end I wrote مهمه rather than مهمة, But that's very strange to me, as Duolingo usually accepts final ة to be written ه ...
Maybe I'm missing something else that I can't see... I just started learning Arabic like one or two months ago, I am by no means a master of the Arabic writing system (not yet, at least)...
I'm not sure how sensitive Duolingo is when it comes to Hamza (many natives in fact neglect it when they type or even don't know when to put it), anyway it should be like this:
At the end, you have the word مهمه which should be مهمة
This mistake, again, many people (natives I mean) do neglect it and would type ـه instead of ـة but in my opinion this is a grave mistake more than the above Hamza because this change can change the whole meaning of the word. Even though the meaning is obvious from the context still, the word can be quite different. In your example, مهمه is a verb meaning (to make one silent, to ask one to be silent) and مهمة is (important/f). Despite the fact that the former is quite classic and people don't use it now in dialect or in literature MSA.
So, these are differences, and I would forgive the Hamza part somehow but not the Ta-Marbutah ة. Not sure on what level does Duolingo work though.