The nested IF statement
A nested IF statement is an IF statement inside an IF statement. The nesting might occur in either part of the IF, and the nested IF may or may not itself be a compound IF statement. Nesting can go to any level.
IF control_expression_1
IF control_expression_2
A nested set of one or more statements
ENDIF
ELSE
IF control_expression_3
A nested set of one or more statements
ELSE
A nested set of one or more statements
ENDIF
ENDIF