On The Town: To go out for a drink with friends to a bar or Disco.
Fib or Tell Porkies: To lie about something. “You are fibbing”, “You are telling porkies”.
Scrap or Scuffle: To have a fight
Drop off: Fall asleep
Croak, Pop Your Clogs, Bought The Farm: To die or drop dead.
Skive or Bunk: Avoid work or not go to class.
Bump: To remove someone from a guestlist.
Suck: To be bad at doing something. “I really suck at speaking English”
Throw the Book At: Punish someone severely. For example, send them to prison. “I will throw the book at you”
Wrap, Cut, Break or Call It a Day: it’s time to finish.