intensify vs lull

intensify

verb
  • To render more intense 

  • To become intense, or more intense; to act with increasing power or energy. 

lull

noun
  • A period of rest or soothing. 

  • A period without waves or wind. 

  • An extended pause between sets of waves. 

  • A period of reduced activity; a respite 

verb
  • To cause to rest by soothing influences; to compose; to calm 

  • To become gradually calm; to subside; to cease or abate. 

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