ul li br invalid why?

mam do indexu pres include vlozeno tohle:

<div id="nav">
<ul>
<?php
echo "<li";
if ($clanek=='NECO') echo " id='aktivni'";
echo "><a href='/mostpopular'>mostpopular(id)</a></li> ";
?>
<?php
echo "<li";
if ($clanek=='NECO') echo " id='aktivni'";
echo "><a href='/newest'>newest(id)</a></li> ";
?>
<br/>
<span class="modra">&not; D</span><span class="bila">ownload</span> <br/>
<li><a href="/mostpopular">most popular</a></li><br/>
<li><a href="/newest">newest</a></li><br/>
<li><a href="/search">search</a></li><br/>
<span class="modra">&not; U</span><span class="bila">pload</span> <br/>
<li><a href="/link">link</a></li><br/>
<li><a href="/test-lomitko/lomitko">test lomitka</a></li><br/>
</ul>
</div><!-- nav -->

toho php si nevsimejte to jen zkousim aktivni linky (na to pudu az po tomhle :)
a validator mi pise 8 chyb (za neco muze wz reklama)

-Error Line 65, Column 4: document type does not allow element "br" here; assuming missing "li" start-tag.
<br/>
One possijavascript:paste_strinL(' [pre][/pre]',0)
Kódble cause for this message is that you have attempted to put a block-level element (such as "<p>" or "<table>") inside an inline element (such as "<a>", "<span>", or "<font>").


-Line 67, Column 14: document type does not allow element "li" here; missing one of "ul", "ol" start-tag.
<li><a href="/mostpopular">most popular</a></li><br/>
One possible cause for this message is that you have attempted to put a block-level element (such as "<p>" or "<table>") inside an inline element (such as "<a>", "<span>", or "<font>").


-Line 73, Column 14: end tag for "li" omitted, but OMITTAG NO was specified.
</ul>
You may have neglected to close an element, or perhaps you meant to "self-close" an element, that is, ending it with "/>" instead of ">".
Info Line 65, Column 0: start tag was here.
<br/>

link Text validace .p

nevite v cem je problem ? dekuju :p

no ja prave v ul mam jen li br a span ne? .. a i když to "obzaviram" ty spany takže mam ul li li /ul span ul .. tak to píše ty stejný chyby tak nevim :(

ježiš aha :) díky moc..