break up vs vow

break up

verb
  • To end a (usually romantic or sexual) relationship with each other. 

  • Of a conversation, to cease to be understandable because of a bad connection; of a signal, to deteriorate. 

  • To dissolve; to part. 

  • To break or separate into pieces. 

  • Become disorganised 

  • Of a school, to close for the holidays at the end of term. 

  • be or cause to be overcome with laughter 

  • To end a (usually romantic or sexual) relationship. 

  • To stop a fight; to separate people who are fighting. 

  • To cut or take to pieces for scrap. 

  • To break or separate into pieces; to disintegrate or come apart. 

  • To upset greatly; to cause great emotional disturbance or unhappiness. 

vow

verb
  • To declare publicly that one has made a vow, usually to show one's determination or to announce an act of retaliation. 

  • To make a vow; to promise. 

  • To make a vow regarding (something). 

noun
  • A solemn promise to perform some act, or behave in a specified manner, especially a promise to live and act in accordance with the rules of a religious order. 

  • A declaration or assertion. 

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