1.对于<a>标签
以前：
<h2><a href="index.html">The home page</a></h2>
<p><a href="index.html">This paragraph also links to the home page</a></p>
<a href="index.html"><img src="home-image.png" alt="home-slice"/></a>
现在可以这么用：
<a href="index.html">
<h2>The home page</h2>
<p>This paragraph also links to the home page</p>
<img src="home-image.png" alt="home-slice"/>
</a>
2.常见的非保留废弃零件有strike, enter, font, acronym, frame和frameset
3语义化元素
<section> <nav> <article> <aside> <hgroup> <header> <footer> <address>
4.文本及语义元素
<b> <em> <i>
5.CSS3多栏布局
column-width
column-count
栏位间隙 column-gap 分隔线 column-rule
6.文字换行
word-wrap:break-word;