陈年旧账

To be honest, you don't talk about the past, no one can remember, today these old accounts are because your previous jokes ran out.

Some head teachers criticize students who violate discipline and like to work out a lot of "old accounts", while turning over old accounts, which is the most repugnant to students.

Come on, I'm not going to turn over these old accounts with you, but as the father of the child, where can you leave it alone?