adopt vs assign

adopt

verb
  • To select and take or approve. 

  • To take voluntarily (a child of other parents) to be in the place of, or as, one's own child. 

  • To take or receive as one's own what is not so naturally. 

  • To obtain (a pet) from a shelter or the wild. 

  • To take by choice into the scope of one's responsibility. 

  • To beat an opponent ten times in a row. 

assign

verb
  • To appoint or select (someone) for some office. 

  • To give (a value) to a variable. 

  • To allot or give (something) as a task. 

  • To designate or set apart (something) for some purpose. 

  • To attribute or sort (something) into categories. 

  • To categorize (someone) as belonging to the male or female sex. 

  • To transfer (property, a legal right, etc.) from one person to another. 

noun
  • An assignee. 

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