knack vs strength

knack

noun
  • A readiness in performance; aptness at doing something. 

  • A petty contrivance; a toy. 

  • Something performed, or to be done, requiring aptness and dexterity. 

verb
  • To speak affectedly. 

strength

noun
  • The quality or degree of being strong. 

  • The intensity of a force or power; potency. 

  • The strongest part of something; that on which confidence or reliance is based. 

  • A positive attribute. 

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