bleat vs sound off

bleat

verb
  • Of a person, to complain. 

  • Of a sheep or goat, to make its characteristic cry; of a human, to mimic this sound. 

noun
  • The characteristic cry of a sheep or a goat. 

sound off

verb
  • To hold forth about something in an opinionated manner. 

  • Command instructing a person to confirm that they are present or that some other objective has been met. 

  • Command instructing a person to speak up or acknowledge something. 

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