anchor.diff:  úi,uj
   úy,uj
   ý,i
  -ă,ă
  +ă,ă
   đ,d
   ĩ,i
   ĩa,iə
  
positive.code: à,a
  ài,aj
  ào,aw
  àu,ăw
  ày,ăj
  á,a
  ái,aj
  áo,aw
  áu,ăw
  áy,ăj
  â,ɤ̆
  âu,ɤ̆w
  ây,ɤ̆j
  ã,a
  ãi,aj
  ão,aw
  ãu,ăw
  ãy,ăj
  è,ɛ
  èo,ew
  é,ɛ
  
negative.code: uẫy,wɤ̆j
  uậ,wɤ̆
  uậy,wɤ̆j
  uắ,wă
  uằ,wă
  uẳ,wă
  uẵ,wă
  uặ,wă
  uẹ,wɛ
  uẹo,wew
  uẻ,wɛ
  