<!DOCTYPE html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>appendTo()方法插入内容</title>
<script src="http://libs.baidu.com/jquery/1.9.0/jquery.js" type="text/javascript"></script>
</head>
<body>
<h3>appendTo()方法插入内容</h3>
<div>
<span class="green">小乌龟</span>
</div>
<script type="text/javascript">
var $html = "<span class='red'>小青蛙</span>"
$("$html").appendTo("div");
</script>
</body>
</html>
这样写的为什么没有效果啊？求指导
