contributive vs promising

contributive

adj

  • Tending to contribute; making a contribution 

promising

adj

  • Showing promise, and likely to develop in a desirable fashion. 

  • a promising young apprentice 

  • Encouraging and inspiring confidence. 

noun

  • The act of making a promise. 

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