imperfect vs past simple

imperfect

noun
  • a tense of verbs used in describing a past action that is incomplete or continuous 

  • something having a minor flaw 

verb
  • to make imperfect 

adj
  • not perfect 

  • belonging to a tense of verbs used in describing a past action that is incomplete or continuous 

  • known or expected to be polyphyletic, as of a form taxon. 

  • unisexual: having either male (with stamens) or female (with pistil) flowers, but not with both. 

past simple

noun
  • simple past 

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