How about this one:
O'Brien meets Winston in The Ministry of Love and says to him, "You knew this, Winston," said O'Brien. "Don't deceive yourself. You did know it--you have always known it." Yes, he saw now, he had always known it (page 197 of the Holt, Rinehart, Winston publication).
In a paragraph or two, explain how Winston had always known that O'Brien was not a member of the resistance. Back up your claims with evidence from the text.