relent vs taper off

relent

verb
  • To slacken; to abate. 

  • To give in or be swayed; to become less hard, harsh, or cruel; to show clemency. 

noun
  • Stay; stop; delay. 

taper off

verb
  • To diminish or lessen gradually; to become smaller, slower, quieter, etc. 

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