In his talk available on YouTube as “Language, Creativity, and the Limits of Understanding” by Professor Noam Chomsky (4-21-16) at 56:36s Noam Chomsky starts talking about the phenomenon of displacement.
While I believe I understand what displacement, reconstruction, and deletion of copies mean I cannot reconcile it with the example given: "Which books did John read?"
Prof. Chomsky says that the sentence is interpreted something like "For which books X John read books X" and later "Which books did John read which books?".
Could you explain this to my simple mind?