continue vs vary

continue

verb
  • To remain in a given place or condition; to remain in connection with; to abide; to stay. 

  • To make a continuation bet. 

  • To retain (someone or something) in a given state, position, etc. 

  • To proceed with (doing an activity); to prolong (an activity). 

  • To make last; to prolong. 

  • To resume. 

  • To adjourn, prorogue, put off. 

noun
  • An option allowing the player to resume play after game over, when all lives have been lost, while retaining their progress. 

vary

verb
  • Not to remain constant: to change with time or a similar parameter. 

  • To make of different kinds; to make different from one another; to diversity; to variegate. 

  • To embellish; to change fancifully; to present under new aspects, as of form, key, measure, etc. See variation. 

  • To be or act different from the usual. 

  • To institute a change in, from a current state; to modify. 

  • To change with time or a similar parameter. 

  • To display differences. 

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