cobol中的write有关问题

cobol中的write问题
我想在一个文件里写入一些记录，代码如下：
DATA DIVISION.
  FILE SECTION.
  FD READFILE LABEL RECORD IS OPEN-R,OPEN-S.
  01 OPEN-R.
  02 OPEN-FIR PIC X(6).
  02 OPEN-SEC PIC X(6).
  02 OPEN-THR PIC X(6).
  01 OPEN-S PIC X(5).
   
  WORKING-STORAGE SECTION.
  01 CNT PIC 9(2).  
   
  PROCEDURE DIVISION.
   
  MOVE 'NEWORD' TO OPEN-FIR.
  MOVE 'SECOND' TO OPEN-SEC.
  MOVE 'THRIDE' TO OPEN-THR.
   
  MOVE 'YUMEN' TO OPEN-S.
   
  OPEN EXTEND READFILE.
  PERFORM VARYING CNT FROM 1 BY 1
  UNTIL CNT IS GREATER THAN 10
  IF CNT < 10
  THEN 
  WRITE OPEN-R AFTER ADVANCING 1 LINES
  ELSE
  CONTINUE
  END-IF
  END-PERFORM.
  WRITE OPEN-S AFTER ADVANCING 1 LINES
  CLOSE READFILE.
其他地方和这里关系不大，所以没贴上来，我得到的文件内容却是这样的：

YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMENDSECONDTHRIDE
YUMEN
其实我想得到的是：
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
NEWORDSECONDTHRIDE
YUMEN

我认为这个程序的逻辑会得到我想要的格式啊 为什么open-r的一部分内容会被open-s的内容覆盖了呢？请帮忙看看，谢谢了！！！


------解决方案--------------------
变量在用的时候没有初始化吧？
------解决方案--------------------
检查变量，应该是初始化问题。