embroil vs explain

embroil

verb
  • To implicate in confusion; to complicate; to jumble. 

  • To draw into a situation; to cause to be involved. 

explain

verb
  • To make plain, manifest, or intelligible; to clear of obscurity; to illustrate the meaning of. 

  • To give a valid excuse for past behavior. 

  • To make something plain or intelligible. 

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