I'm not sure of the model that Duolingo is using but in Arabic, the sentence is flexible - but there is the "norm" and there is the "literature" or "eloquence" versions or styles.
Just to add, there are two types of sentences: Nominal and Verbal. Away from the extensive studies that had been done on such classification but the most modern one and what is taught in schools is: Nominal sentence is a sentence that stars with a Noun, and Verbal is the sentence that starts with a verb. But things can be quite flexible. Just an example:
Ahmad went to the market - I can state this in various ways:
ذهب أحمد إلى السوق
أحمد ذهب إلى السوق
إلى السوق ذهب أحمد
إلى السوق أحمد ذهب
أحمد إلى السوق ذهب
Changing the order of the words does not change the meaning but changes the rhyme and the sounds. However, the most normal and common one would be the first and second ones: ذهب أحمد إلى السوق (literal: went/Ahmad/to/the market), or أحمد ذهب إلى السوق (literal: Ahmad/went/to/the market). The first is Verbal version, and the second is Nominal version.
all works providing the words declension is done properly. In Nominal sentences in Arabic you can have a sentence starting out without any verbs at all; e.g. الشمس مشرقة (aš-šamsu mušriqatun: the sun is shining). In English you have to use (is) to connect the sentence but in Arabic you don't use any verbs. Literally, the sentence is: the sun/shining - and Shining here is considered to be another noun, in the place of a predicative.
I don't read newspapers usually, but i don't think they are differ much from the general literature.
No not really. Nominal and verbal sentences are 2 common features for the Arabic language (and its dialects) In general. Nominal sentences specifically had been a subject for studies from old times to modern times and many things had been said about its classification (i.e. when to consider a sentence nominal: Arabic: جملة اسمية Jumlah Ismiyyah). However, the most accepted method right now and what is taught in schools is that a sentence is called nominal or verbal depending on the word which starts it. Example:
- الشمس أشرقت (al-šamsu ašraqat) - the sun had risen. This is nominal because it started with الشمس (the sun), a feminine noun.
- أشرقت الشمس (ašraqat al-šams) - The sun had risen (again), but this is a verbal sentence because it started with a verb أشرقت (rose/had risen).
Things won't stop here, a nominal sentence can be made up without any verb at all: e.g. الشمس مشرقة (al-šamsu mušriqatun), the sun is rising.
There are some theories though that says it is common for an Arabic speaker to bring to attention the focal point of the sentence to the beginning. That is, in our first sentence الشمس أشرقت I am bringing the attention of the listener to the sun الشمس because I want to talk about it, because it is the important or focal point of my speech. Same thing for the opposite, if I started with the verb أشرقت, it's like I want to bring the attention of the listener to the action of the sun. In English, though, both sentence would more or less be translated the same: the sun had risen.
In dialects, I would say both type of sentences are used, but maybe not into the context I've just mentioned above, but probably more into a personal style of speech. Like, me personally, I find myself tending more to start a sentence with a noun rather than a verb, most of the time. Some might do the opposite and so on.
Your answer is a genitive phrase and not a complete sentence.
In English, there is a difference between Arwa has a new cat and Arwa's new cat. The first one is a full sentence stating a fact or information about (what does Arwa has), while the second sentence is simply a genitive relation between words (X of Y, Cat of Arwa) - there is no (to be) verb.
This same concept applies to Arabic:
- Arwa has a new cat: عند أروى قطة جديدة.
- Arwa's new cat: قطة أروى الجديدة.
First of all, ignore the audio. It is wrong in its spelling.
The letter ة is actually a merge of 2 sounds. It's called Ta'-Marbúta تاء مربوطة (tied Ta). Most feminine words end with this letter. In isolated form or when the word comes at the end of the sentence (where dropping the last vowel in the word is permitted, MSA-wise) this letter gains its "H" sound. Thus, قطة at the end of the sentence would be (QiTTah).
Anyway, when the word ending with this letter needs to be moved with the vowel at its end (i.e. declined), this "H" changes to "T" automatically. For example, if I want to say (the cat of Arwa), which is a genitive relation between CAT and ARWA, then it would be قِطّةُ أروى (QiTTatu Arwá).
As for the -un (or -an, or -in) sound at the end of some words, this is actually called Tanwin or Nunation. It is one of the types of vowels and for some reason I don't know, Duolingo is not using the marks for this Tanwin on letters. Anyway, to keep it short, you can think of Tanwin or Nunation as a mark for indefinite nouns, just like the English a/an before an indefinite word. Example:
The cat: القطةُ (al-qiTTatu).
A cat: قطةٌ (qiTTatun).
Hope this clarifies things. And by the way, in the audio, the speaker (which is automated) should say (qiTTatun jadeedatun) and not (qiTTatan jadeedatan).
Well, grammatically speaking, yes. As in any language, grammar is grammar and it is there to rectify and guide the usage of the language.
However, in Arabic and with the spread of dialects, it is not critical. This is what Duolingo-Arabic is about actually as I noticed; They are merging dialectical Arabic with Standard Arabic on many occasions. In dialects, the last vowels are almost always omitted and grammar is not strict. So, your suggested sentence would still be understood by an Arab.