code: private final boolean cvc(int i) {
          if (i < 2 || !cons(i) || cons(i-1) || !cons(i-2))
              return false;
          char ch = sb.charAt(i);
          return !(ch == 'w' || ch == 'x' || ch == 'y');
      }
docs: /* cvc(i) is true <=> i-2,i-1,i has the form consonant - vowel - consonant
  and also if the second c is not w,x or y. this is used when trying to
  restore an e at the end of a short word. e.g.
  
  cav(e), lov(e), hop(e), crim(e), but
  snow, box, tray.