Easy. Something like:
10 DATA 1,2,3,4,5
15 FOR I=1 TO 5
20 READ A,B,C,D,E
30 PRINT A,B,C,D,E
40 RESTORE 10 ! or just RESTORE
50 NEXT I
The bug will show when it hits the RESTORE statement in line 40. You'll get an error. It has been a while since I did this...