1 DO
2 %repetitor
3 %conditional ;
4? 
4+ 
4 instruction
5 END
6? name
7 ;
8 %repetitor
9 name=expri
9.1? TO exprt
9.2? BY exprb
9.3? FOR exprf
9 FOREVER
9 exprr

conditional

1 WHILE exprw
1 UNTIL expru