complain vs tremble

complain

verb
  • To creak or squeak, as a timber or wheel. 

  • To make a formal accusation or bring a formal charge. 

  • To express feelings of pain, dissatisfaction, or resentment. 

tremble

verb
  • To shake, quiver, or vibrate. 

  • To fear; to be afraid. 

noun
  • A shake, quiver, or vibration. 

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