We use this question when we want to check and see how confident or sure the other person is about what they said or what they will do.

We can use this question to make sure that some information is correct.

• Are you sure that it will rain today?
• Are you sure that this is her phone number?

We can also use this question to make sure a person is confident in their decision.

• Are you sure that you want to quit your job?
• Are you sure that investing in that company is a good idea?

The short version would be "Are you sure?" or "Are you sure about that?", but if we want to be very clear about what we are referring to, then we can use the sentence pattern below.

Are you sure (that) + sentence?

Even though this is a question, the second part of this pattern (the "sentence" part) is in regular sentence form.

• Are you sure that the restaurant is open on Sunday?
• Are you sure this coat is on sale? I don't see any signs.
• Are you sure that the bank is closed today?
• Are you sure he doesn't want to come?
• Are you sure that he works here?
• Are you sure that this is the right place?
• Are you sure it is not too late?
• Are you sure that the store is open?
• Are you sure that he is awake?
• Are you sure she will like this necklace?
• Are you sure that Mr. Smith will approve this project?
• Are you sure that the President will do that?

It is possible to change the subject of the sentence.

• Is Ben sure that he doesn't want to join us for dinner?
• Is Mark sure the museum is closed on Mondays?
• Are Tina and Sue sure that they want to live together?
• Are the police sure that he was the one who stole the diamonds?

Bonus Tips and Points

1. We can use the words "positive" or "certain" instead of "sure".

• Are you positive that the restaurant is open now?
• Are you positive she is Mark's sister?
• Are you certain that Mary lives here?
• Are you certain the stock market will crash this year?

2. We can ask a similar question using, "How sure are you that…?". This question is asking how confident a person feels about something.

A) How sure are you that this will be successful?
B) I am very sure. I promise that this will be a big hit.

A) How sure are you that she will come?
B) I am pretty sure.

A) How sure are you that this will work?
B) To be honest, I am not sure at all. We will have to wait and see.

Real-World English Conversations

A) Are you sure that you want to quit your job?
B) Yes. I have thought a lot about it, and I think it is the right decision.
A) Then you should do it.

A) Is he sure that he doesn't want to come to the party?
B) He says he has too much work, but if he finishes early, then he will come.

A) Are you sure that he is married?
B) I think so, but I am not sure. We can ask Karen. She knows him well.

A) I am moving to LA and I am going to be an actor.
B) Are you sure that is a good idea?
A) I don't know, but it is my dream so I have to try.

A) The restaurant opens at 8 am.
B) Are you sure that it opens that early? They don't serve breakfast.
A) You may be right. Let me call and check.

A) Are you sure that he said that?
B) That's what everybody told me.

Study these free English lessons to improve your English speaking. If you learn these common sentence patterns well, then your English speaking will improve greatly and you will be able to have fluent conversations in English in the near future! Study the lessons well, practice using them at home and in real life, and make sure to come back to review the material so you do not forget.