enter vs start doing

enter

verb
  • To become effective; to come into effect. 

  • To go or come into (a state or profession). 

  • To become a party to an agreement, treaty, etc. 

  • To cause to go (into), or to be received (into); to put in; to insert; to cause to be admitted. 

  • To place in regular form before the court, usually in writing; to put upon record in proper from and order 

  • To go into or upon, as lands, and take actual possession of them. 

  • To deposit for copyright the title or description of (a book, picture, map, etc.). 

  • To go or come into an enclosed or partially enclosed space. 

  • To type (something) into a computer; to input. 

  • To record (something) in an account, ledger, etc. 

  • To make report of (a vessel or its cargo) at the custom house; to submit a statement of (imported goods), with the original invoices, to the proper customs officer for estimating the duties. See entry. 

start doing

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