嵌套的表格怎么没显示！
  <td>
  <%
        java.util.List   list=(java.util.List)request.getAttribute( "courseList ");
        if(!list.isEmpty())
        System.out.println( "非空 ");  
        java.util.Iterator   iter=list.iterator();
      while(iter.hasNext())
      {
shsc.lbh.vo.Course   course=(shsc.lbh.vo.Course)iter.next();
System.out.println(course.getId());
System.out.println(course.getCnum());
System.out.println(course.getCname());
System.out.println(course.getXuefen());
System.out.println(course.getXingzhi());
System.out.println(course.getSeason());
      }
  %>
      <table   border= "1 ">
        <th> <font   size= "6 "   color= "blue "> <b> 课程号 </b> </font> </th>
        <th> <font   size= "6 "   color= "blue "> <b> 课程名 </b> </font> </th>
        <th> <font   size= "6 "   color= "blue "> <b> 学分 </b> </font> </th>
        <th> <font   size= "6 "   color= "blue "> <b> 性质 </b> </font> </th>
        <th> <font   size= "6 "   color= "blue "> <b> 季节 </b> </font> </th>
        <logic:present   name= "courseList "   scope= "request ">
          <logic:iterate   id= "course "   name= "courseList "   type= "shsc.lbh.vo.Course "   scope= "request ">
                  <tr>
                        <td> <bean:write   name= "course "   property= "cnum "/> </td>
                        <td> <bean:write   name= "course "   property= "cname "/> </td>
                        <td> <bean:write   name= "course "   property= "xuefen "/> </td>
                        <td> <bean:write   name= "course "   property= "xingzhi "/> </td>
                        <td> <bean:write   name= "course "   property= "season "/> </td>
                  </tr>
          </logic:iterate>
        </logic:present>
      </table>
  </td>
为什么上面打印出了内容,表格怎么没有显示？？？麻烦大家看一下楼，谢谢！！

------解决方案--------------------
<thead> <tr>
<th> <font size= "6