功能存储在数据库中，这就是为什么即使您删除了功能，它们仍保持活动状态。需要明确删除功能：

$admin  = get_role(\'author\');
$admin->remove_cap( \'edit_teacher\' );

而且，由于它们存储在数据库中，您应该停止在每次页面加载中添加它们（就像您在中所做的那样init 事件）。通常，您应该在插件激活挂钩上添加自定义功能，并在插件停用时删除这些功能：

add_action(\'init\',\'plugin_main_functions\');
function plugin_main_functions(){
  register_post_type(\'teachers\', array(
    \'labels\' => array(
        \'name\'=>__(\'Teachers List\', \'Teachers\'),
        \'add_new\' => __(\'add new teacher\', \'Teachers\'),
        \'add_new_item\' => __(\'Add new teacher\', \'Teachers\')
        ),
    \'public\' => true,
    \'supports\'=> array(\'title\', \'editor\', \'thumbnail\'),
    \'menu_icon\' => \'dashicons-groups\',
    \'capability_type\' => array(\'teacher\',\'teachers\'),
    \'map_meta_cap\' => true

  ));

}

register_activation_hook( __FILE__, function () {

    // Call function plugin_main_functions(),
    // The function where the custom post type is registered
    plugin_main_functions();

    $admin = get_role(\'administrator\');

    $admin->add_cap(\'edit_teacher\');
    $admin->add_cap(\'edit_teachers\');
    $admin->add_cap(\'read_teacher\');
    $admin->add_cap(\'delete_teacher\');
    $admin->add_cap(\'delete_teachers\');
    $admin->add_cap(\'publish_teacher\');
    $admin->add_cap(\'create_teachers\');

    flush_rewrite_rules();

} );

register_deactivation_hook( __FILE__, function () {

    // Call function plugin_main_functions(),
    // The function where the custom post type is registered
    plugin_main_functions();

    $admin = get_role(\'administrator\');

    $admin->remove_cap(\'edit_teacher\');
    $admin->remove_cap(\'edit_teachers\');
    $admin->remove_cap(\'read_teacher\');
    $admin->remove_cap(\'delete_teacher\');
    $admin->remove_cap(\'delete_teachers\');
    $admin->remove_cap(\'publish_teacher\');
    $admin->remove_cap(\'create_teachers\');

    flush_rewrite_rules();

} );

然后，如果需要在插件激活时在其他事件中修改功能，则应在添加/删除功能之前进行一些检查，以避免执行不必要的数据库操作。

例如：

add_action(\'init\',\'plugin_main_functions\');
function roles_to_edit_teacher(){
    if( $i_neet_to_remove_cap === true ) {
        $admin = get_role(\'administrator\');
        $admin->remove_cap(\'some_capability\');
    }
    if( $i_neet_to_add_cap === true ) {
        $admin = get_role(\'administrator\');
        $admin->add_cap(\'some_capability\');
    }
}