be up to vs entertain

be up to

verb
  • To depend on, to be the choice of. 

  • To do or be involved in doing; to do (often something mischievous or inappropriate). 

entertain

verb
  • To receive and take into consideration; to have a thought in mind. 

  • To have someone over at one's home for a party or visit. 

  • To amuse (someone); to engage the attention of agreeably. 

How often have the words be up to and entertain occurred in a corpus of books? (source: Google Ngram Viewer )