Questions & Answers about Niby wszystko jest w katalogu.
Niby is a tricky little word. It often means something like supposedly, apparently, so they say, or kind of, depending on context.
In Niby wszystko jest w katalogu, it adds a shade of doubt, skepticism, or irony. The speaker is not simply stating a fact. They are suggesting something like:
- Apparently everything is in the catalogue...
- Everything is supposedly in the catalogue...
- In theory, everything is in the catalogue...
So the sentence does not sound fully confident. It implies that maybe, in practice, something is missing or the situation is not as clear as it should be.
Because wszystko is grammatically treated as singular in Polish.
So you say:
- Wszystko jest ... = Everything is ...
not:
- Wszystko są ... ❌
Even though everything refers to many things in meaning, the word wszystko itself behaves like a singular neuter subject, so it takes jest.