帮忙修改一段代码，我是不会，急用啊！

<BODY> 
<TABLE width="274" border="1" align="center" cellpadding="0" cellspacing="0" id="tbl_persons" style="table-layout:fixed"> 
<TR bgcolor="buttonface">
<TD width="8"></TD>
<TD width="308">编号</TD>
</TR>
<TR>
<TD colspan="2"><INPUT TYPE="checkbox" NAME="chkPerson">
  1
  ,
  <INPUT TYPE="checkbox" NAME="chkPerson">
    2
    ,
    <INPUT TYPE="checkbox" NAME="chkPerson">
    3
    ,
    <INPUT TYPE="checkbox" NAME="chkPerson">
    4</TD>
  </TR>
</TABLE>
<BR>
<div align="center"><button onclick="fnReturnItem()">选 择</button> &nbsp;<button onclick="window.close();">取 消</button></div> 
</BODY>
</HTML>
<script language="javascript">
function fnReturnItem()
{
var arrChk = document.getElementsByName("chkPerson");
if (typeof (arrChk) == 'object')
{
var src_Table = document.getElementById("tbl_persons");
var dest_Table = window.opener.tbl_grid;
for (var i=0; i<arrChk.length; i++)
{
if (arrChk[i].checked)
{
 var tbRow = dest_Table.insertRow();
                 var src_row = src_Table.rows(i + 1);
                 var tbCell = tbRow.insertCell();
                 tbCell.innerText = src_row.children(1).innerText;
                 tbCell = tbRow.insertCell();
                 tbCell.innerText = src_row.children(2).innerText;
                 tbCell = tbRow.insertCell();
                 tbCell.innerText = src_row.children(3).innerText;
                 tbCell = tbRow.insertCell();
                 tbCell.innerHTML = "<span style='width:100%' contentEditable='true' onblur='makeSum(this)'>0</span>";
                 tbCell = tbRow.insertCell();
                 tbCell.align = "right";
                 tbCell.innerText = "0.00";
}
}
}
window.close();
}
是这样吗？