/*
  if input (how many terms do we have?)
  and ($n = numberOfTermsInMainIndex())
  then say (We have $n shortened terms.)
*/
static S rule_numberOfTerms() {
  ai_checkInput_match3("how many terms do we have?");
  long n = numberOfTermsInMainIndex();
  ret replaceVars2("We have $n shortened terms.", "$n", formatWithThousands(n));
}