Ja-/Nein-Frage or Yes-/No-Question is a type of question, to which we can answer in no or yes.
But German language has 3 answers to this kind of question: ja, nein, doch.
For example:
Bist du Manager hier? Nein, ich bin Kellner hier.
Are you manager here? No, I am waiter here.
Bist du Manager hier? Ja, ich bin Manager hier.
Are you manager here? Yes, I am manager here.
And then, there is third type of Ja-/Nein-Frage, when the question itself contains a negative tag. So, if you want answer this question in ‘no’, you simply answer in with a ‘nein’. For example:
Bist du nicht Manager hier? Nein, ich bin Kellner hier.
But, if you want to answer this question in ‘yes’, you answer with ‘doch’. For example:
Bist du nicht Manager hier? Doch, ich bin Manager hier.
Are you manager here? Of course, I am manager here.
Click here to practice the topic: https://wordwall.net/de/resource/13527321/niemiecki/ja-nein-doch