Kein and nicht
When do you use kein and nicht? Are they interchangeable? Or do they need to be used with specific verbs?
"nicht" goes with nouns with definite articles (die, der, das, etc.) and "kein" replaces the article in nouns with indefinite articles (eine, etc.) and uses the same ending scheme. "nicht" will also go with verbs "Ich esse nicht," not "Ich esse kein," but you would have "Ich esse kein Fleisch" or "Ich werde(will) nicht die Wurst essen" referring to a particular sausage(determined). Also if there is not article, use "kein": "Ich habe Zeit" -> "Ich habe keine Zeit".
Basically, if there is important information in the article, you use "nicht" (i.e. it's not indefinite)
I'm not a German native so the above could be wrong.
I noticed when translated "The man doesn't like groups" Duolingo accepts "Der Mann mag keine Gruppen" but not "Der Mann mag nicht Gruppen". The meaning of these seems interchangeable with the former meaning "The man likes no groups" and the latter meaning "The man doesn't like groups".
As a native speaker I can say "Der Mann mag nicht Gruppen" is wrong. But never thought about it.
Correct would be "Der Mann mag keine Gruppen" meaning he does not like any groups. "Der Mann mag diese Gruppen nicht." meaning he does not like some of the groups.
What I looked up is you use "keine" if you have an indefinite artice and use "nicht" when you use a definite article. And additionally when you are counting, you use "nicht" with the number. "Der Mann mag drei Gruppen nicht."
I am pretty sure there are some cases I am not aware of. But that should help in general.