This should do it:
$text = __( '<strong><a href="https://wordpress.stackexchange.com/questions/268780/%1$s">login</a> or <a href="https://wordpress.stackexchange.com/questions/268780/%2$s">register</a> to be able to add new adverts</strong>', 'adverts' );
printf( '<div>' . $text . '</div>', wp_login_url(), wp_registration_url());