exempt vs set free

exempt

verb
  • To grant (someone) freedom or immunity from. 

adj
  • Free from a duty or obligation. 

  • Not entitled to overtime pay when working overtime. 

noun
  • One of four officers of the Yeomen of the Royal Guard, having the rank of corporal; an exon. 

  • One who has been released from something. 

  • A type of French police officer. 

set free

verb
  • To release, to free, to give freedom to. 

How often have the words exempt and set free occurred in a corpus of books? (source: Google Ngram Viewer )