involve vs let out

involve

verb
  • To complicate or make intricate. 

  • To take in; to gather in; to mingle, blend or merge. 

  • To cause or engage (someone or something) to participate or to become connected or implicated. 

  • To comprise or include; to have as a related part. 

  • To envelop, enfold, entangle. 

let out

verb
  • To enlarge by adjusting one or more seams. 

  • Of a school: to finish for the day or term, allowing the pupils to go home. 

  • To disclose. 

  • To rent out. 

  • Of sound, to emit. 

  • To allow to operate at higher speed by adjusting controls. 

  • To release. 

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