Hi, i know i'm about 3 years too late, but i would like to clarify that i did not mean "y'all" as a literal translation for the hebrew. "yall" does not exist in hebrew, but a single word (in both the male and female form) for "you all" does. Some english speakers, though, do not say you all because of dialects and regional culture and instead they say y'all. That is all I meant. I was more so translating my already translated english into slang english lol. I did not type y'all into Duolingo thinking it should accept it.
As far as I understand, it's the whims of each language, and not some strict logic, that determines the existence of collective nouns. It's just luck that both English and Hebrew have a collective noun for cows (cattle, בקר). No such luck with "fruit" (possibly a collective noun), where Hebrew has only the countable noun פרי with the plural פירות. (Actually there is also a collective usage of פרי, I think mainly in contexts of commerce and agriculture (הרבה פרי)).
As was said, "morning" is written differently, but do expect to have many pairs of unrelated words written the same and sound either the same or differently! (Triplets, too.) It happens in English, too, BTW ("read" in present vs. past tense; "can" the verb vs. the noun), but a lot more common in Hebrew.