    public static function html() {
        new Xaptcha();
        $html = "<div class=\"form-group\">
            <div class=\"g-recaptcha\" data-sitekey=\"".self::$key."\"></div></div>
            <script type=\"text/javascript\"
                    src=\"https://www.google.com/recaptcha/api.js?hl=".self::$lang."\" async defer>
            </script>";
        if (self::isEnable()) {
            return $html;
        }else{
            return '';
        }
    }

The software constructs all or part of an SQL command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended SQL command when it is sent to a downstream component.