Expressing certainty and uncertainty

Certainty and uncertainty

Certainty is the state of being completely confident or having no doubt about something. However, uncertainty is when nothing is ever decided or sure.

Expressing certainty

When you are sure that something will or will not happen in the future, use these expressions.

For example to the question:
"Will John pass the exam?"
you may respond as follows:

Expressing uncertainty

When you are not sure whether something or someone will or will not happen, use the following expressions.
For example, to the question:
"Will John follow a career in business?"
you may respond as follows:

Well,

it's possible, it's impossible, it might be, it might not be, it could happen,

I suppose,

but

I wouldn't like to say for certain. I'm not sure I doubt it. I have my own doubts. it's doubtful. It's highly / very unlikely.

you never know of course, no one can know for certain.

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