RULE "4 Epenthesis,  0:0 /<= [Csib|ch|sh|y:i] +:0___s [+:0|#]"  6 8
   c h s Csib y + # @
   c h s Csib i 0 # @
1: 2 1 4 3    3 1 1 1
2: 2 3 3 3    3 1 1 1
3: 2 1 3 3    3 5 1 1
4: 2 3 3 3    3 5 1 1
5: 2 1 6 3    3 1 1 1
6: 2 3 4 3    3 0 0 1