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IF/ELSE in COBOL reads like English:

           IF AGE >= 18
               DISPLAY "adult"
           ELSE
               DISPLAY "minor"
           END-IF.

Note: NO period inside the IF (would terminate the statement). End with END-IF.

EVALUATE is COBOL's switch:

           EVALUATE GRADE
               WHEN "A"
                   DISPLAY "excellent"
               WHEN "B" THRU "D"
                   DISPLAY "passing"
               WHEN OTHER
                   DISPLAY "failed"
           END-EVALUATE.

Loops via PERFORM:

           PERFORM VARYING I FROM 1 BY 1 UNTIL I > 10
               DISPLAY I
           END-PERFORM.

PERFORM ... TIMES for fixed counts:

           PERFORM 5 TIMES
               DISPLAY "hi"
           END-PERFORM.

PERFORM can also call paragraphs (named code blocks) — COBOL's primitive procedure mechanism.