forgo vs retain

forgo

verb
  • To refrain from, to abstain from, to pass up, to withgo. 

  • To let pass, to leave alone, to let go. 

  • To do without, to abandon, to renounce. 

retain

verb
  • To hold back (a pupil) instead of allowing them to advance to the next class or year. 

  • To employ by paying a retainer. 

  • To keep in one's pay or service. 

  • To keep in possession or use. 

  • To hold secure. 

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