plight vs undertake

plight

verb
  • To promise (oneself) to someone, or to do something. 

  • Specifically, to pledge (one's troth etc.) as part of a marriage ceremony. 

noun
  • Blame; culpability; fault; wrong-doing; sin; crime. 

  • One's office; duty; charge. 

  • Responsibility for ensuing consequences; risk; danger; peril. 

  • A dire or unfortunate situation. 

  • An instance of danger or peril; a dangerous moment or situation. 

undertake

verb
  • To commit oneself (to an obligation, activity etc.). 

  • To pass a slower moving vehicle on the curbside rather than on the side closest to oncoming traffic. 

  • To take upon oneself; to start, to embark on (a specific task etc.). 

noun
  • The passing of slower traffic on the curbside rather than on the side closest to oncoming traffic. 

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