Cách sử dụng
"Fess up" is a colloquial expression that means to confess or admit to something that you have done wrong or that you are hiding. It is often used when someone is suspected of doing something they shouldn't have, or when they are caught in a lie. For example, if your teacher catches you cheating on a test, they might say "Fess up, did you cheat?" which means "Admit it, did you cheat?". It's an informal, more conversational way of asking someone to be honest and upfront about something.