[Blackadder thinks Nurse Mary is a German spy.]
Captain Blackadder: And then the final, irrefutable proof. Remember, you mentioned a clever boyfriend...
Nurse Mary: Yes.
Captain Blackadder: I then leapt on the opportunity to test you. I asked if he'd been to one of the great universities, Oxford, Cambridge, or Hull.
Nurse Mary: Well?
Captain Blackadder: You failed to spot that only two of those are great Universities.
Nurse Mary: Swine!
General Melchett: That's right! Oxford's a complete dump!