act as middle vs negotiate

act as middle

negotiate

verb
  • To succeed in coping with, or getting over something. 

  • To arrange or settle something by mutual agreement. 

  • To transfer to another person with all the rights of the original holder; to pass, as a bill. 

  • To confer with others in order to come to terms or reach an agreement. 

How often have the words act as middle and negotiate occurred in a corpus of books? (source: Google Ngram Viewer )