inflect vs leave alone

inflect

verb
  • To influence in style. 

  • To vary the form of a word to express tense, gender, number, mood, etc. 

  • To change the tone or pitch of the voice when speaking or singing. 

  • To cause to curve inwards. 

  • To be varied in the form to express tense, gender, number, mood, etc. 

leave alone

verb
  • To desist or refrain from involvement with. 

  • To stop bothering (a person). 

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