Question tags (..., can't he/doesn't he?)
Positive statements with auxiliaries (HWW; they go with another/lexical verb - ZWW): can/could/will/would/shall/should/must/may/might/is/are/was/were/has/have
-> use the negative auxiliary behind the comma/in the question tag: can't, couldn't, won't etc.
She will call me later, won't she?
Positive statements with a lexical verb (verb can stand on its own/has meaning on its own, e.g.drink, dance, study, work, do etc.)
-> use doesn't/don't/didn't + the infinitive/1st form behind the comma/ in the question tag
Look at the person (singular/plural)
Look at the tense
They ate very little, didn't they?
She makes rude comments, doesn't she?
Negative statements take a positive question tag
She won't call, will she? They didn't eat a lot, did they?