"Tuesday is after Monday."
Translation:Salı, pazartesiden sonra.
"Sonra pazartesi salıdır" is wrong. Because it hasn't any meaning in Turkish.
Actually, according to me, the translate "Salı, pazartesiden sonra." is wrong as well. Instead of this, "Salı, pazartesiden sonraDIR." or (for "Tuesday comes after Monday") we can say "Salı, pazartesiden sonra gelir." / "Pazartesiden sonra salı gelir."
I thought about this and I am not quite sure but as far as I know it's like this:
pazartesi = Monday -> pazartesiden
arabası = his car -> arabasından
'pazartesi' does not have an ending while 'araba' has the possessive ending '-sı' where you need a buffer 'n' before attaching another suffix.