请问怎么判断子栏目的第一个，并为它加上样式

<table width="100%" border="0" cellspacing="0" cellpadding="0" class="box">
<tr>
<td>
<ul class="nymainleftul01">
[e:loop={"select classid,classname from {$dbtbpre}enewsclass where bclassid={$class_r[$GLOBALS[navclassid]][bclassid]} order by myorder,classid asc",0,24,0}]
<?php
$classurl=sys_ReturnBqClassname($bqr,9);
if($GLOBALS[navclassid]==$bqr[classid]){
?>
<li><a class="choose" href="<?=$classurl?>"><?=$bqr[classname]?></a></li>
<?php }else{ ?>
<li><a href="<?=$classurl?>"><?=$bqr[classname]?></a></li>
<?php } ?>
[/e:loop]
</ul>
</td>
</tr>
</table>