public function getUserLng($user_id = 0)
    {
        $user_id = (int)$user_id;

        $preferred_language = $this->getUserData('lng', $user_id);

        // Check if exists selected
        $languages = Languages::getPairs();
        if (!isset($languages[$preferred_language])) {
            // Get first language
            $preferred_language = key($languages);
        }

        return $preferred_language;
    }