is it ok to say "I will know"?
Is it alright to use phrase "I will know" instead of "I understand", "got it", "understood" or "okay"?
For example,
- Let's go eat something.
- Go without me.
- Why?
- I never eat after 9 p.m.
- I will know!

Question

Answer

Hi Roman!

Typically we wouldn't say "I will know". The other examples you gave work very well (e.g. "I understand"). Another response you can also use is "I see".

Hope that helps!

Answer

No, we can't use 'I will know' in this way. It would seem very strange, to the English-speaking ear, to use a future in this context.

You could say 'I see', or just 'OK' or 'Right'.