cut down vs lengthen

cut down

verb
  • To bring down by cutting. 

  • To insult, to belittle. 

  • Used other than figuratively or idiomatically: see cut, down. 

  • To reduce the amount of something. 

lengthen

verb
  • To become longer. 

  • To make longer, to extend the length of. 

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