The traditional pattern is:
Mittagessen = Lunch in German
lunch - das Mittagessen
Wienerschnitzel
i don't know after dinner, after lunch, at lunch, at dinner i guess.
They became french
don t know what to have for lunch
esse diene Mittagessen
Laß uns zu Mittag essen
You can say Guten Appetit or Mahlzeit.
Haben Sie gegangen für Mittagessen
have lunch
The Canadian 3rd Infantry Division and Canadian 2 Armoured Brigade landed there and crushed the German defenders before lunch.