Print only vowels from a given word.(SUB)

DECLARE SUB DISPLAY(N$)
CLS
INPUT"ENTER ANY NUMBER";N$
CALL DISPLAY(N$)
END

SUB DISPLAY"(N$)
FOR I=1 TOO LEN(N$)
B$=MID$(N$,I,1)
C$=UCASE$(B$)
IF C$="A" OR C$"E" OR C$="I"  OR C$="I" OR C$="O" OR C$="U" THEN D$=D$+B$
NEXT I
PRINT"VOWELS=";D$
END SUB