carp vs sound off

carp

verb
  • To complain about a fault; to harp on. 

noun
  • Any of various freshwater fish of the family Cyprinidae, especially the common carp, Cyprinus carpio. 

sound off

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

  • 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. 

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