public function string($key, $language = '')
    {
        if (!$this->hasTranslations()) {
            return $this->container['lang'][$key];
        }

        if ($language == '') {
            $language = I18N::getCurrent();
        }

        if (array_key_exists('lang_' . $language, $this->container)) {
            return $this->container['lang_' . $language][$key];
        }

        return '';
    }