guess
‘guess’
If you guess that something is true, you decide that it is probably true.
By this time they'd guessed that something was seriously wrong.
You also use guess to say that someone finds the correct answer to a problem or question without knowing that it is correct.
I guessed what was going to happen at the end of the film.
‘I guess’
In conversation, you can say I guess when you think that something is true or likely.
I guess he got stuck in traffic.
‘What’s that?' – ‘Some sort of blackbird, I guess.’
You can use I guess so in conversation as an informal way of answering yes. Don't say ‘I guess it’.
‘Can you find some information for me?’ – ‘I guess so.’
‘Does that answer your question?’ – ‘Yeah, I guess so.’
You can use I guess not in conversation as an informal way of answering no, or of answering yes to a negative question.
‘So no one actually saw him arriving?’ – ‘No, I guess not.’
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