employ vs enroll

employ

verb
  • To hire (somebody for work or a job). 

  • To use (somebody for a job, or something for a task). 

  • To make busy. 

noun
  • The state of being an employee; employment. 

enroll

verb
  • To enlist (someone) or make (someone) a member of 

  • To enlist oneself (in something) or become a member (of something) 

  • To enter (a name, etc.) in a register, roll or list 

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