1、从IE9开始到后继的版本都支持HTML5，那么怎么让IE9以下的版本支持HTML5呢？
这里有一个JS文件，源文件如下：
(function(k,m){var g="3.7.0";var d=k.html5||{};var h=/^<|^(?:button|map|select|textarea|object|iframe|option|optgroup)$/i;var c=/^(?:a|b|code|div|fieldset|h1|h2|h3|h4|h5|h6|i|label|li|ol|p|q|span|strong|style|table|tbody|td|th|tr|ul)$/i;var q;var i="_html5shiv";var a=0;var o={};var e;(function(){try{var t=m.createElement("a");t.innerHTML="<xyz></xyz>";q=("hidden" in t);e=t.childNodes.length==1||(function(){(m.createElement)("a");var v=m.createDocumentFragment();return(typeof v.cloneNode=="undefined"||typeof v.createDocumentFragment=="undefined"||typeof v.createElement=="undefined")}())}catch(u){q=true;e=true}}());function f(t,v){var w=t.createElement("p"),u=t.getElementsByTagName("head")[0]||t.documentElement;w.innerHTML="x<style>"+v+"</style>";return u.insertBefore(w.lastChild,u.firstChild)}function l(){var t=j.elements;return typeof t=="string"?t.split(" "):t}function p(t){var u=o[t[i]];if(!u){u={};a++;t[i]=a;o[a]=u}return u}function n(w,t,v){if(!t){t=m}if(e){return t.createElement(w)}if(!v){v=p(t)}var u;if(v.cache[w]){u=v.cache[w].cloneNode()}else{if(c.test(w)){u=(v.cache[w]=v.createElem(w)).cloneNode()}else{u=v.createElem(w)}}return u.canHaveChildren&&!h.test(w)?v.frag.appendChild(u):u}function r(v,x){if(!v){v=m}if(e){return v.createDocumentFragment()}x=x||p(v);var y=x.frag.cloneNode(),w=0,u=l(),t=u.length;for(;w<t;w++){y.createElement(u[w])}return y}function s(t,u){if(!u.cache){u.cache={};u.createElem=t.createElement;u.createFrag=t.createDocumentFragment;u.frag=u.createFrag()}t.createElement=function(v){if(!j.shivMethods){return u.createElem(v)}return n(v,t,u)};t.createDocumentFragment=Function("h,f","return function(){var n=f.cloneNode(),c=n.createElement;h.shivMethods&&("+l().join().replace(/[\w\-]+/g,function(v){u.createElem(v);u.frag.createElement(v);return'c("'+v+'")'})+");return n}")(j,u.frag)}function b(t){if(!t){t=m}var u=p(t);if(j.shivCSS&&!q&&!u.hasCSS){u.hasCSS=!!f(t,"article,aside,dialog,figcaption,figure,footer,header,hgroup,main,nav,section{display:block}mark{background:#FF0;color:#000}template{display:none}")}if(!e){s(t,u)}return t}var j={elements:d.elements||"abbr article aside audio bdi canvas data datalist details dialog figcaption figure footer header hgroup main mark meter nav output progress section summary template time video",version:g,shivCSS:(d.shivCSS!==false),supportsUnknownElements:e,shivMethods:(d.shivMethods!==false),type:"default",shivDocument:b,createElement:n,createDocumentFragment:r};k.html5=j;b(m)}(this,document));
2、还需要在页面中添加样式，样式内容如下：
article,aside,dialog,footer,header,section,footer,nav,figure,menu{display:block}