enlighten vs frustrate

enlighten

verb
  • To make something clear to (someone); to give knowledge or understanding to. 

  • To supply with light. 

frustrate

verb
  • To disappoint or defeat; to vex by depriving of something expected or desired. 

  • To cause stress or annoyance. 

  • To hinder or thwart. 

adj
  • ineffectual; useless; fruitless. 

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