asp 怎么自动提取关键词（帮忙修改代码）

<table width="90%" border="0" cellspacing="0" cellpadding="3" align="center">            
            <form method="post" action="" name="form1">
                <tr>
                <td width=18% align=right height=30>标 题：</td>
                <td width=82%> <input type="text" name="title" size="70" value="科学家计划在撒哈拉沙漠兴建世界级太阳能发电站" /></td>
              </tr>
                <tr>
                <td width=18% align=right height=40>关键词：</td>
                <td width=82%> <input type=text id="tags" name="tags" size="40" />　<input type="button" onclick="lastIndexDemo();" value="提 取" /></td>
              </tr>
              <tr>
                <td width=18% height=60></td>
                <td width=82%> <input type="submit" value=" 提 交 " name="add"></td>
              </tr>
           </form>
</table>