Are you sure?
Are you sure about that?
Are you sure of what you said?
Are you sure that he is not coming?
I've had so many problems with my new car.It's diving crazy.
Are you sure you don't want to buy a new one.
How can I? I already spent a lot of money on this.
I guess you'll spending a lot of money on then.
I guess so . Unless you want to buy a car.
No thanks.I don't think I buy your car. It has many problems.
I don't blame you. It's a piece of junk.