Question

Expressions of certainty and uncertainty ?

Answer 1

Certainty = yakin.
Uncertainty = tidak yakin/ragu.
Asking certainty·         
Are you sure that -blablabla-?     
Are sure about -blablabla-?·         
Do you think that -blablabla-?·         
How do you so sure?·         
Are you positively sure?
Respond or express certainty·         
Yes, it confirmed·         
I am definitely sure·         
Of course·         
Sure, I am certain·         
I have no doubt about it
Giving Uncertainty·         
I am not sure·         
I am not certain of it·         
I doubt of it·         
I afraid that it is wrong·         
Sorry, I am not sure about it

Answer 2

Expressing Certainty 
- Yes, it confirmed
- I am definitely sure
- Of course
- Sure, I am certain
- I have no doubt about it

Expressing Uncertainty
- I am not sure
- I am not certain of it
- I doubt of it
- I afraid that it is wrong
- Sorry, I am not sure about it

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