SVG -如何使多个元素同时运动？

<svg xmlns="http://www.w3.org/2000/svg" width="400" height="400">
  <rect x="50" y="50" width="100" height="100">
    <animate attributeName="x" from="50" to="200" dur="2s" repeatCount="indefinite" />
  </rect>
  <circle cx="200" cy="200" r="50">
    <animate attributeName="cy" from="200" to="100" dur="2s" repeatCount="indefinite" />
  </circle>
</svg>

<svg xmlns="http://www.w3.org/2000/svg" width="400" height="400">
  <style>
    @keyframes moveX {
      from { transform: translateX(0); }
      to { transform: translateX(200px); }
    }
    @keyframes moveY {
      from { transform: translateY(0); }
      to { transform: translateY(100px); }
    }
    rect {
      animation: moveX 2s infinite alternate, moveY 2s infinite alternate;
    }
  </style>
  <rect x="50" y="50" width="100" height="100"></rect>
</svg>