answer: #Person2# tells #Person1# that a girl is all Greek to #Person2# means #Person2# couldn't understand her at all.
documents: #Person1#: Does she make any sense to you? 
  #Person2#: No. It's all Greek to me. 
  #Person1#: She's speaking French, not Greek. 
  #Person2#: I know that. I mean I couldn't understand her at all. 
  #Person1#: Me neither. All I have to do is study French hard. 
  #Person2#: I wish you the best of luck.