validation

I have the following validation errors. Please advice how to fix them. I appreciate any assistance.
Line 152, column 39: document type does not allow element “form” here; assuming missing “li” start-tag
<form action=”/index.php” method=”get”>
Line 169, column 5: end tag for “li” omitted, but OMITTAG NO was specified

Line 152, column 1: start tag was here
<form action=”/index.php” method=”get”>