二级分类及文章列表：

{eyou:channelartlist typeid='3'}
{eyou:channel type="son"}
{$field.typename}<!-- 二级栏目名称 -->
{eyou:arclist typeid='$field.typeid'}
<a href="{$field.arcurl}">{$field.title}</a>
{/eyou:arclist}
{/eyou:channel}
{/eyou:channelartlist}

三级分类及文章列表：

{eyou:channelartlist typeid='3'}
{eyou:channel type="son" id='field2'}
<a href="{$field2.typeurl}">{$field2.typename}</a>
{eyou:channel name="$field2.children" id='field3'}
<a href="{$field2.typeurl}">{$field3.typename}</a>
{eyou:arclist typeid='$field.typeid' titlelen='20' id="field3"}
<a href="{$field3.arcurl}"><img src="{$field3.litpic}">{$field3.title}</a>
{/eyou:arclist}    
{/eyou:channel}
{/eyou:channel}    
{/eyou:channelartlist}

注意field，field2，field3的用法