我已经创建了自定义帖子类型，本月和下月创建了两个帖子类别，并为每个类别分配了示例帖子。预览类别存档时/分类/本月有一个页面未显示任何内容，因此我假设该页面存在，但帖子未显示。问题是，我如何才能使分配给帖子类别的帖子在say/category/this month上显示？

// Register Custom Post Type
function activity() {

    $labels = array(
        \'name\'                  => _x( \'Activity\', \'Post Type General Name\', \'twenty_two\' ),
        \'singular_name\'         => _x( \'Activity\', \'Post Type Singular Name\', \'twenty_two\' ),
        \'menu_name\'             => __( \'Activity\', \'twenty_two\' ),
        \'name_admin_bar\'        => __( \'Activity\', \'twenty_two\' ),
        \'archives\'              => __( \'Item Archives\', \'twenty_two\' ),
        \'attributes\'            => __( \'Item Attributes\', \'twenty_two\' ),
        \'parent_item_colon\'     => __( \'Parent Product:\', \'twenty_two\' ),
        \'all_items\'             => __( \'All Activity\', \'twenty_two\' ),
        \'add_new_item\'          => __( \'Add New Activity\', \'twenty_two\' ),
        \'add_new\'               => __( \'New Activity\', \'twenty_two\' ),
        \'new_item\'              => __( \'New Item\', \'twenty_two\' ),
        \'edit_item\'             => __( \'Edit Activity\', \'twenty_two\' ),
        \'update_item\'           => __( \'Update Activity\', \'twenty_two\' ),
        \'view_item\'             => __( \'View Activity\', \'twenty_two\' ),
        \'view_items\'            => __( \'View Items\', \'twenty_two\' ),
        \'search_items\'          => __( \'Search Activity\', \'twenty_two\' ),
        \'not_found\'             => __( \'No Activity found\', \'twenty_two\' ),
        \'not_found_in_trash\'    => __( \'No products found in Trash\', \'twenty_two\' ),
        \'featured_image\'        => __( \'Featured Image\', \'twenty_two\' ),
        \'set_featured_image\'    => __( \'Set featured image\', \'twenty_two\' ),
        \'remove_featured_image\' => __( \'Remove featured image\', \'twenty_two\' ),
        \'use_featured_image\'    => __( \'Use as featured image\', \'twenty_two\' ),
        \'insert_into_item\'      => __( \'Insert into item\', \'twenty_two\' ),
        \'uploaded_to_this_item\' => __( \'Uploaded to this item\', \'twenty_two\' ),
        \'items_list\'            => __( \'Items list\', \'twenty_two\' ),
        \'items_list_navigation\' => __( \'Items list navigation\', \'twenty_two\' ),
        \'filter_items_list\'     => __( \'Filter items list\', \'twenty_two\' ),
    );
    $args = array(
        \'label\'                 => __( \'Activity\', \'twenty_two\' ),
        \'description\'           => __( \'Display activities post\', \'twenty_two\' ),
        \'labels\'                => $labels,
        \'supports\'              => array( \'title\', \'editor\', \'thumbnail\' ),
        \'taxonomies\'            => array( \'category\', \'post_tag\' ),
        \'hierarchical\'          => false,
        \'public\'                => true,
        \'show_ui\'               => true,
        \'show_in_menu\'          => true,
        \'menu_position\'         => 5,
        \'show_in_admin_bar\'     => true,
        \'show_in_nav_menus\'     => true,
        \'can_export\'            => true,
        \'has_archive\'           => \'activities\',
        \'exclude_from_search\'   => false,
        \'publicly_queryable\'    => true,
        \'capability_type\'       => \'page\',
    );
    register_post_type( \'activity\', $args );

}
add_action( \'init\', \'activity\', 0 );