1.
<hgroup> <h1></h1> <h2> </h2> <h3></h3></hgroup>
代码如下：
1 <!doctype html> 2 <html> 3 <head> 4 <meta charset="utf-8"> 5 <title>介绍青花瓷</title> 6 </head> 7 8 <body> 9 <hgroup> 10 <h1>1.初识html5</h1> 11 <h2> 1.1 </h2> 12 <h3>1.11介绍</h3> 13 <h3>1.12基本结构</h3> 14 <h3>1.13组成框架</h3> 15 </hgroup> 16 </body> 17 </html>测试结果：
转载于:https://www.cnblogs.com/Catherinezhilin/p/8830246.html
