be still vs tremor

be still

tremor

verb
  • To shake or quiver excessively and rapidly or involuntarily; to tremble. 

noun
  • An earthquake. 

  • A shake, quiver, or vibration. 

  • A rhythmic, uncontrollable shaking of all or part of the body due to partial muscle contractions. 

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