"You read the menu."
Translation:Siz menüyü okursunuz.
Actually, it's not about sen or siz. It's more about the suffix on okur.
In case of you, the suffix is -sIn or -sInIz.
"Sen menuyu okursun", if there is only one person; and
"Siz menuyu okursunuz", if there are more than two persons, or if you are addressing only person but formally or respectfully.