anchor.diff:  kidney,kidneys
   knife,knives
   leaf,leaves
  -lice,lice
  +louse,lice
   linguistics,linguistics
   life,lives
   loaf,loaves
  
positive.code: stadiums,stadiums
  stereo,stereos
  stimulus,stimuli
  succubus,succubi
  swine,swine
  syllabus,syllabi
  
negative.code: antenna,antennas
  appendix,appendices
  athletics,athletics
  attorney,attorneys
  axis,axes
  bacillus,bacilli
  baggage ,baggage 
  