Translation:She sells everything that is pastry.
I think this is another example of Duolingo English (Dinglish?) -- a string of words that are recognisably English but no native English speaker would every come up with
Thank you. Uhm, well, that account (AronTrinidad) uses my old email. One time, my Facebook and Twitter accounts got hacked and, you know posted some real SPG posts, so I have to deactivate everything and make a new email. For my own security, I made a new Duolingo account too. If the mods were to deactivate AronTrinidad, well, be my guest.
That does not make sense in English. Nor, for that matter, does, "She sells everything that is pastry" - at least from my perspective. Not sure what Duo is going for here.
Edit: I guess I was going down the wrong track, and the adjective/noun debate doesn't matter. Sorry. I would never say "pastry" without either "a" or "the" preceding it. Or, at least in this sentence. I don't know. I give up.
"pastry" can be a countable noun (like "cow") or an uncoutable (like "milk").
- The cabinet is full of pastries
- The cabinet is full of pastry
Both are correct English. A pastry is something that is made out of pastry.
"She sells all things pastry" is far more natural selling than "she sells everything that is pastry" which I highly doubt any English speaker has ever said unless complaining about this particular question on duolingo.