是否可以对链接应用自定义分类法？如果是，怎么做？

我已经这样做了，但似乎不起作用：

$labels = array(
    \'name\'                       => _x( \'Lessons\', \'Taxonomy General Name\', \'text_domain\' ),
    \'singular_name\'              => _x( \'Lesson\', \'Taxonomy Singular Name\', \'text_domain\' ),
    \'menu_name\'                  => __( \'Lesson\', \'text_domain\' ),
    \'all_items\'                  => __( \'All Lesson Lessons\', \'text_domain\' ),
    \'parent_item\'                => __( \'\', \'text_domain\' ),
    \'parent_item_colon\'          => __( \'\', \'text_domain\' ),
    \'new_item_name\'              => __( \'New Lesson\', \'text_domain\' ),
    \'add_new_item\'               => __( \'Add new Lesson\', \'text_domain\' ),
    \'edit_item\'                  => __( \'Edit Lesson\', \'text_domain\' ),
    \'update_item\'                => __( \'Update Lesson\', \'text_domain\' ),
    \'separate_items_with_commas\' => __( \'Separate Lessons with commas\', \'text_domain\' ),
    \'search_items\'               => __( \'Search Lessons\', \'text_domain\' ),
    \'add_or_remove_items\'        => __( \'Add or remove Lessons\', \'text_domain\' ),
    \'choose_from_most_used\'      => __( \'Choose from the most used Lessons\', \'text_domain\' ),
    \'not_found\'                  => __( \'Not Found\', \'text_domain\' ),
);
$args = array(
    \'labels\'                     => $labels,
    \'hierarchical\'               => true,
    \'public\'                     => true,
    \'show_ui\'                    => true,
    \'show_admin_column\'          => true,
    \'has_archive\'                => true,
    \'show_in_nav_menus\'          => true,
    \'show_tagcloud\'              => true,
);
register_taxonomy( \'lesson\', array( \'post\',\'portfolio\',\'link\', \'forum\' ), $args );

马可