您可以使用两个查询，第一个查询可以获得如下分类：

$categories = get_categories();

foreach($categories as $cat)
{
    //get the $n posts from this category
    $post_query = new WP_Query(
        array(\'post_type\' => \'post\',
          \'posts_per_page\' => $n ,
          \'tax_query\' => array(
                array(
                  \'taxonomy\' => $cat->taxonomy,
                  \'field\'    => \'slug\',
                  \'terms\'    => $cat->term_id,
               )
         )
       )
    );
    echo \'<h2>\'.$cat->name.\'</h2>\';
    while($post_query->have_posts()){
       $post_query->the_post();
       echo get_the_title();
    }wp_reset_query();
}