pursue vs undertake

pursue

verb
  • To aim for, go after (a specified objective, situation etc.). 

  • To follow, travel down (a particular way, course of action etc.). 

  • To follow urgently, originally with intent to capture or harm; to chase. 

  • To participate in (an activity, business etc.); to practise, follow (a profession). 

  • To act as a legal prosecutor. 

undertake

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

  • 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. 

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

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