CERTAINTY and UNCERTAINTY

Expressing Certainty and Uncertainty in English

If you are sure or not sure about something, you can use below phrases and expressions to express your Certainty/Uncertainty.

Asking for Certainty:

 Are you sure?

 Are you sure about it?

 Are you certain about it?

 Do you think it is true?

 Do you think so?

 How sure are you?

Expressing Certainty:

 Yes, I am certain.

 I’m a hundred percent certain …

 I’m absolutely sure.

 I have no doubt about it.

 I’m sure about it.

 I don’t think there can be any doubt about ….

 Of course.

 I’m positive.

 I’m quite sure about it.

 I’m no doubt about it.

 I’m absolutely certain that…

Expressing Uncertainty:

 I’m not sure about it.

 I doubt it.

 I’m not really sure about…

 I don’t know for sure…

 It’s very unlikely.

 I have my own doubts.

 I don’t think so.

 I don’t believe this is true.

 There’s some doubt in my mind that …

 I’m not a hundred percent sure.

 I don’t know yet.