The major difference between Html5 and xHTML is Html5 add more tag element,such as ‘<header>’ , ‘<nav>’….and so on.

We use these tag elements ,we also notice these tag element whether use in old browser at the same time. There I have one way to solve this problem.

First, we can use javascript to create element. Second,use css make this element become a “block” element(In other words,they can display on the web page)

As follows：

[javascript]

<!--[if IE]-->  
<script type="text/javascript">
document.createElement("header");
document.createElement("footer");
document.createElement("section");
document.createElement("aside");
document.createElement("nav");
document.createElement("article");
document.createElement("hgroup");
document.createElement("time");
</script>
<!--[endif]-->

[css]

section,header,footer,section,aside,nav,article,hgroup,time{
display:block
}