    hi<!DocType "some stuff>">hi
    hi<!DocTypE 'more stuff>'>hi
    hi<!dOCtYPE>hi
    hi<!dOcTyPeStuff>hi
    hi<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">hi
    hi<!doctype 'stuff'>hi

    hi<!--comment-->hi
    hi<!--<tag>-->hi
    hi<!--false close>-->hi
    hi<! --comment-- >hi
    hi<!--comment-- --comment2-->hi

    <!--Some-Formatted Text Examples-->
    hi<pre>This is pre-formatted.</pre>hi
    hi<PrE><tag></tag></PRe>hi
    hi<PRE></></p></pR></pRee></pretag></Pre>hi
    hi<pre><!--  -->"stuff"'hello'//*=
    //!@#$><%^&*(){}~|\"-</pRe>hi
    hi<pre><<<<</pre>hi
    hi<pre></p</p</pre>hi
    hi<pre><<</p<<</pre>hi
    hi<pre><</pr<</ PR</Pre </pre>hi
    hi<pre><</pre<</ pre </pre>hi
    hi<pre></pre>hi
    hi<pre><</pre>hi
    hi<pre></pre>hi
    hi<pre align=left some></pre>hi

    <!--Some Client Side Scripting Examples-->
    hi<script>This is a script</script>hi
    hi<sCript><tag></tag></scriPt>hi
    hi<SCRIPT></></s></SC></sCr></ScRi></SCRIP>
    </scripttag></SCRIPTTAG></scRIpttag></Script>hi
    hi<sCRIPT><!--  -->"stuff"'hello'//*=
    //!@#$><%^&*(){}~|\"-</sCrIpT>hi
    hi<sCRIPT><!-- </script> --></sCrIpT>hi
    hi<scripT><<<<</scriPt>hi
    hi<scripT></s</s</scriPt>hi
    hi<scripT><<</s<<</scriPt>hi
    hi<scripT><</scrI<</ SCR</ScRIpt </scriPt>hi
    hi<scripT><</scrI<</ SCR </scriPt>hi
    hi<scripT></SCRIPT</SCR</Sc</scriPt>hi
    hi<scripT></scriPt>hi
    hi<scripT><</SCriPt>hi
    hi<scripT></SCriPt>hi

    <!--Some Server Side Scripting Examples-->
    hi<? echo ("this is the simplest, an SGML processing instruction\n"); ?>hi
    hi<?php echo("if you want to serve XML documents, do like this\n"); ?>hi
    hi<script language="php"> hi
    	echo ("some editors (like FrontPage)
    	don't like processing instructions");
    </script>hi
    hi<% echo ("ASP-style tags"); %>hi
    hi<%= $variable; # This is a shortcut for "<%echo .." %>hi
    hi<? echo ("hello"); ??>hi
    hi<? echo ("hello"); ???>hi
    hi<??>hi
    hi<?>?>hi
    hi<???>hi
    hi<????>hi
    hi<% echo ("hello"); %%>hi
    hi<% echo ("hello"); %%%>hi
    hi<%%>hi
    hi<%>%>hi
    hi<%%%>hi
    hi<%%%%>hi

    hi<tag>hi
    hi<my.tag-your.tag>hi
    hi<tag name>hi
    hi<tag 2name>hi
    hi<tag .name>hi
    hi<tag -name>hi
    hi<tag name=value>hi
    hi<tag name=3value>hi
    hi<tag name=.value>hi
    hi<tag name=-value>hi
    hi<tag name1=value1 name2=value2>hi
    hi<tag name1=value1 name2 name3=value3 name4>hi
    hi<tag name1 = value1 name2 name3 = value3 >hi
    hi<tag name='value'>hi
    hi<tag name="value">hi
    hi<tag name=">">hi
    hi<tag name='>'>hi

    hi</end>hi
    hi</ end >hi

    hi&nbsp;hi&lt;hi&#23345;hi&#xf2;hi&#XFa33;hi&quot<tag>hi&amp
    hi&pi&nu&mu

    The following may be represented as error:
    hi&unknown;hi&NBSP;hi&LT;hi

    Everything else definitly has errors:
    hi<!--comment1-- notComment --comment2-->hi
    hi<!not legal>hi
    hi<!-not legal>hi
    hi<!- not legal>hi
    hi<! -not legal>hi
    hi<!dnot legal>hi
    hi<!Donot legal>hi
    hi<!DoCnot legal>hi
    hi<!DoCtypnot legal>hi
    hi< tag>hi
    hi<1tag>hi
    hi<.tag>hi
    hi<-tag>hi
    hi<$tag>hi
    hi<tag_>hi
    hi<ta#g>hi
    hi<tag *name>hi
    hi<tag n<ame>hi
    hi<tag name|>hi
    hi<tag name=""">hi
    hi<tag name='''>hi
    hi<tag name=%value>hi
    hi<tag name=val&ue>hi
    hi<tag name=value)>hi
    hi<script language=>this<that</script>hi
    hi</>hi
    hi</=end>hi
    hi</en;d>hi
    hi</end:>hi
    hi</end end>hi
    hi<tag name=>hi

    <open