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<!DOCTYPE html>
<html>
<body>
<h1>设置 HTML</h1>
<div id="01">
  <h2>Hello China!</h2>
</div>
<div id="02">
  <h2>Hello World!</h2>
</div>
<script>
var content = document.getElementById("01").innerHTML;
document.getElementById("02").innerHTML = content;
</script>
</body>
</html>