In the lovely moment where Vorg speaks to the Doctor in 'Carni' (to test if he is of carnival origin) the actor speaks Polari, which is a real world form of slang. It is a mixture of pidgin Italian, rhyming slang, and Romany. Roughly translated, what he says is:
"Do you speak Carni?"
"Look at this beautiful girl."
"There is no money round here, you understand."
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