<svg width="200" height="100" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <rect width="100" height="100" fill="green">
        <animate attributeName="x" values="0; 100; 0" dur="1s" repeatCount="indefinite"></animate>
    </rect>
</svg>