typedef enum { one, two, three } etype; 
typedef enum { cero, uno, dos } stype; 
typedef enum _ietag { siete } itype; /* 11. enum _ietag specified but not defined */

typedef struct { int a; int b; } st;
typedef struct { int a; int b; int c; } st2; /* (5. Field  present in spec...) */

enum { hasta, pasta, yasta } ;