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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8"> 
<title>Wfuyu教程(wfuyu.com)</title>
<script src="http://libs.baidu.com/jquery/1.10.2/jquery.min.js">
</script>
<script>
$(document).ready(function(){
  $("button").click(function(){
    $("ul li:first-child").hide();
  });
});
</script>
</head>
<body>
​
<p>List 1:</p>
<ul>
  <li>Coffee</li>
  <li>Milk</li>
  <li>Tea</li>
</ul>
​
<p>List 2:</p>
<ul>
  <li>Coffee</li>
  <li>Milk</li>
  <li>Tea</li>
</ul>
​
<button>点我</button>
​
</body>
</html>