"The guests do not eat lunch."
Translation:Die Gäste essen kein Mittagessen.
In German it is very common to say for instance just "wir essen Mittag". To say "wir essen Mittagessen" is redundant. Please add this.
When there's an object, you need 'essen kein'. Wir essen kein Eis, Mittagessen, Gemüse, keine Katzen oder Hunde. Without an object, you might say something like 'wir essen nicht' or 'ich esse gar nichts'.
You can't say "ich mag kein dich" because you can't say "ein dich" just like you can't say "zwei dich", "drei dich" etc. It's not something you can count. But you can say "one lunch", "two lunches", "ein Mittagessen", "zwei Mittagessens" so you should say "kein Mittagessen"
I've just read that Mittag can be used as an "abbreviation" but I still don't understand the "zu" on the middle. Could anyone explain this please?
Could you please provide the exact phrases you mean? I guess you mean something like: "Die Gäste essen nicht zu Mittag." or something?
You can say:
"ich esse Mittag" - "I eat lunch"
"ich esse zu Mittag" - equivalent to "I eat at lunch time (and I do it)."
"ich bin zu Mittag" - "I am out for lunch" or "I am at lunch"
All three are meaning the same.
There is, in a way. 'kein'/'keine'/'kein' is the negation of 'ein'/'eine'/'ein'.