copulate vs share a bed

copulate

verb

  • To engage in sexual intercourse. 

adj

  • Joining subject and predicate; copulative. 

share a bed

verb

  • To engage in sexual intercourse (with someone). 

  • Used other than figuratively or idiomatically: see share, bed. 

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