"Od dziś do niedzieli"

Translation: From today to Sunday

[AnnaHaillay]

What's wrong with up to Sunday?

[Jellei]

Nothing, added now.

[PauloSanto801520]

Dziś has no declensions? Why?

[alik1989]

I'd say it's an adverb, which functions as a noun in this sentence. And adverbs never inflect for case.

[VladislavR698109]

Is this some kind of a proverb?

[Jellei]

Not any I'm familiar with.

[Sheilagq]

From today till sunday (short for until)

[Jellei]

It's listed as accepted.

[FrankCzarn]

From today until Sunday not accepted?

[Jellei]

It's listed as accepted.