1. May I borrow this book? - Sure. Just remember to give it back in a week. 2. May I borrow this book? - Sure. Just remember to give it back within a week.
------------------------------ In this short dialogue, does 'in' mean 'within'? Or are both different?
they are both different because, within a week they are supposed to give it back before it is more than a week, it is a regulation, while in a week, you can go a bit higher with a few days.
