We all know how annoying it can be when someone tries to get you to demonstrate a skill you'd rather not perform. Well, here's a cartoon from the excellent Itchy Feet travel and language comic by Malachi Rempen which illustrates that situation.
The cartoon uses a joke much loved by children, who, when asked to say (whatever), just repeat the word or words (whatever). For example, "Say you're sorry." "You're sorry."