Aren’t I?

The question tag for I am is aren’t I, not amn’t I.

I am late, aren’t I? (NOT I am late, amn’t I?)

Imperative sentences

The question tag for imperative sentences are will you/ won’t you/ can you
/ can’t you/ would you / could you.

Come here, will you?
Open the windows, would you?
Keep quiet, can’t you?
Shut up, won’t you?

The question tag for a negative imperative is will you?

Don’t forget, will you?

Let’s

After let’s… we use shall we?

Let’s go for a walk, shall we?

Sentences containing negative words like hardly, never, no, nobody and little are followed by non-negative tags.

You never call me, do you? (NOT …don’t you?)
He is no good, is he? (NOT …isn’t he?)
I have hardly ever met her, have I?

In question tags referring to nothing and everything we use it.

Everything is ok, isn’t it? (NOT …isn’t everything?)
Nothing can happen, can it? (NOT …can nothing?)

In question tags referring to nobody, somebody, everybody etc., we use they.

Nobody came, did they? (NOT …did nobody?)
Somebody wanted a drink, didn’t they?

After principal verb have, question tags with have and do are often both possible. Note that do is more common in American English.

They have a farm house, haven’t / don’t they?
He had a bad headache, hadn’t/didn’t he?

Notes

In sentences with question tags, pronoun subjects and auxiliary verbs are often left out.

Nice day, isn’t it. (More natural than ‘It’s a nice day, isn’t it?)