Turkish soups are always liquid. If it is thick or has chunks it is not corba but yemek. I just saw a post from a friend on Facebook about this -- she is American married to a Turk and he objects that she calls thick soups "soup!" She tells him they are not corba, but they are soup!
About the together/on their own aspect: same applies to English with certain nouns. E.g. you can both say "The BBC has sacked Jeremy Clarkson" and "The BBC have sacked Jeremy Clarkson". The difference is that in the first example you talk about the BBC as a collective: the British Broadcasting Company, and in the second example as the 'board' of the BBC, consisting out of multiple people, who have all decided to not put up with Jeremy Clarkson anymore.
The pronunciation of the last vowels seem to vary here. Selcen_Ozturk, could you let me know if I'm right or if it's just a quirk in the TTS? I hear "birayi" with pure "a" & "i" sounds for the last two vowels. However, at the end but corbayi, the a sounds like "uh" and the i sounds like "oo" (as in good/look/book/took).
Is this due to the difference in the beginning of the words (i.e. bir- vs corb-). If so, I'd love to nail it right from the beginning. :) Tessekurler!