求教高手：用jquery怎么实现我这个表格可以动态添加删除修改？

<html>
<HEAD>
<script type="text/javascript" src="lang/jquery-1.3.2.min.js"> </script> <script type="text/javascript">
        $(document).ready(function() {
        
})
</script>
</head>
<body>
<table id="sist" border="1">
<thead> <tr> 
     <th ><font  size=2>姓名</font></th>
<th ><font  size=2>学号</font></th>
<th ><font  size=2>性别</font></th>
<th ><font  size=2>出生日期</font></th>

</tr>
</thead>
 <tbody>
    <tr>
        <td>1</td>
        <td>2</td>
        <td>3</td>
        <td>4</td>
    </tr>
    <tr>
        <td>11</td>
        <td>22</td>
        <td>33</td>
        <td>44</td>
    </tr>
    <tr>
        <td>111</td>
        <td>222</td>
        <td>333</td>
        <td>444</td>
    </tr>
    <tr>
        <td>1111</td>
        <td>2222</td>
        <td>3333</td>
        <td>4444</td>
    </tr>
    <tr>
        <td>11111</td>
        <td>22222</td>
        <td>33333</td>
        <td>444444</td>
    </tr>
 </tbody>
</table>
<div class="stu">
<input id="addRow" type="Button" value="追加" onclick="addtr()"> 
<input type="Button" value="变更" onclick="edit('test')"> 
<input type="Button" value="保存" onclick=""> 
<input type="Button" value="删除" onclick="deltr('test')"> </div>
</html>
</html>