excite vs tone down

excite

verb
  • To arouse or bring out (e.g. feelings); to stimulate. 

  • To cause an electron to move to a higher than normal state; to promote an electron to an outer level. 

  • To energize (an electromagnet); to produce a magnetic field in. 

  • To stir the emotions of. 

tone down

verb
  • To relax; to make quieter or less obtrusive; to make milder. 

  • To make a television program, piece of writing, etc. less offensive and so more suitable for a family audience. 

  • To moderate or relax; to diminish or weaken the striking characteristics of; to soften. 

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