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编辑您的代码：
<html> <head> <script type="text/javascript"> function newColor(color) { document.getElementById('x').style.background=color } </script> </head> <body> <p>本例演示如何改变 textarea 的背景颜色。</p> <p>请把鼠标移动到下面的三个表格单元上，背景颜色将会改变：</p> <table width="100%"><tr> <td bgcolor="red" onmouseover="newColor('red')"> </td> <td bgcolor="blue" onmouseover="newColor('blue')"> </td> <td bgcolor="green" onmouseover="newColor('green')"> </td> </tr></table> <form> <textarea id="x" rows="5" cols="20"> This example can not be edited because our editor uses a textarea for input, and your browser does not allow a textarea inside a textarea.