"Σήμερα είναι Δευτέρα και αύριο είναι Τρίτη."

[RichDaley]

This is possibly the first Duolingo thing where the options are all grammatically correct but only one option is logically correct!

[Nivkotzer]

Nice :p

[Liebert_]

I'm so glad that the days of the week in Greek language is a bit similar to ordinal numbers. It's so easy to remember. :)

[lfd]

Why not ‘Today it is Monday and tomorrow it is Tuesday’?

[jaye16]

The subject is "Today" using "it" would be like saying "Jane she is a girl."