He is an engineer. Isn’t he?
Positive statement, negative tag

They’re not from Colorado. Are they?
Negative statement, positive tag

Zack is really tired. Isn’t he?
>Positive statement, negative tag

She is going to Taiwan, isn’t she?
Positive statement, negative tag

You have never been to Las Vegas. Have you?
Negative statement, positive tag

 

 

You went to the supermarket. Didn’t you?
Positive statement, negative tag

Zane doesn’t live in Missouri. Does he?
Negative statement, positive tag

Ms. Zeller has a new car. Doesn’t she?
Positive statement, negative tag

The Rays are playing the Jays. Aren’t they?
Positive statement, negative tag

In tag questions, the corresponding pronoun and the first verb of the corresponding yes/no question are used. Also, notice that with positive statements, negative tag questions are used and vice versa.

See also: Grammar: Yes/No Questions

 

Common mistakes:

You are the zookeeper. Yes You’re the zookeeper. Aren’t you? You come from Canada. No? You come from Canada. Don’t you? You’re the boss. Are you? You’re the boss. Are you? Simon is from Singapore. Isn’t it? Simon is from Singapore. Isn’t he?

(Incorrect) (Correct) (Incorrect) (Correct) (Incorrect-in most situations) (Correct) (Incorrect) (Correct)

Some modals can be used in tag questions:

 

I’m the winner. Aren’t I?
Common usage

I’m the winner. Am I not?
Formal