Grammar Tips. Comma 11.

A comma should be used before a question tag. Question tags are the short questions that we put on the end of sentences.

Question tags, also known as tag questions or tail questions, are short phrases added to the end of a sentence to turn it into a question or to seek confirmation or agreement. They are commonly used in English for various purposes. Here are some examples of question tags:

1. It's a nice day, isn't it?

2. You don't mind, do you?

3. We're going to the party tonight, aren't we?

4. He won't be late, will he?

5. She's a great singer, isn't she?

6. They've already left, haven't they?

7. You haven't seen this movie, have you?

8. The concert was fantastic, wasn't it?

9. He can swim, can't he?

10. You wouldn't lie to me, would you?

In these examples, the tag questions seek confirmation or agreement from the listener. The tag usually mirrors the main part of the sentence, so if the main sentence is positive, the tag will be negative, and vice versa. 

INCORRECT: You don’t believe me do you?

CORRECT: You don’t believe me, do you?

INCORRECT: We are going to take the shortcut right?

CORRECT: We are going to take the shortcut, right?