If the subject is nothing, we always use an affirmative question tag:
Something is wrong, isn't it?
Nothing can be done, can it?
• In sentences with everybody, everyone, no one or nobody as the subject, we use a question tag with the pronoun they and the plural form of the verb. If the subject is no one or nobody, we always use an affirmative question tag:
Everybody/Everyone will ask questions, won't they?
Nobody/No one signed up for the dressmaking course, did they?
• In sentences with the pronoun that as the subject, we use a question tag with the pronoun it:
That's your new car over there, isn't it?
• In sentences with there is/there are (in all tenses), we repeat the pronoun there in the question tag:
There was a security alarm in the store, wasn't there?
There won't be any problems with the complaint, will there?
REPLY QUESTIONS:
We use reply questions to show interest in what somebody is saying and to signal that we want more details.
Affirmative [Bevestigende] sentence + affirmative reply question:
'You: 'I went to the new shop in Green Street yesterday.' - 'Your (speaking) partner: 'Did you?'
'Your dad lent me some money.' - 'Did he?'
Negative sentence + negative reply question:
'Chris and Lisa aren't flying to Japan after all.' - 'Aren't they?'
'I never buy shoes online.' - 'Don't you?'