A tag question is a question which we add to the end of a statement because we would like to get an answer to our statement.

The tag contains a subject pronoun (it, he, she, etc.) which matches the subject of the statement, and a verb which matches the verb in the statement.

If the statement is positive the tag is negative.
If the statement is negative the tag is positive.

It's very nice weather today, isn't it?

It isn't a very nice weather today, is it?

She can speak English, can't she?

She can't speak English, can she?

You have finished the work, haven't you?

You haven't finished the work, have you?

He will arrive on time, won't he?

He won't arrive on time, will he?

You know him, don't you?

You don't know him, do you?

He earned a lot of money, didn't he?

He didn't earned much money, did he?

There is enough time, isn't there?

There isn't enough time, is there?

Less usual tag questions

Imperative

Be careful, won't you?

Don't be late, will you?

After let's

Let's go to the cinema, shall we?