Where are you putting the opening and closing of the form? That could well be the cause of the problem. Also, I can't tell if you're using OO style or "standard" style CGI, since you're using shortcuts, but also $query->textfield().

Here's an example that should work, presuming you're not using any other fields in the same form, and that you're using shortcuts consistently (that is, that you have use CGI qw(:standard):

print start_form(),
    table(
    Tr(
        th( 'Column' ),
        th( 'Headings' ),
    ),
    Tr(
        td( textfield('keywords') ),
        td( 'top right' ),
    ),
    Tr(
        td( 'bottom left' ),
        td( 'bottom right' ),
    ),
    end_form();
[download]

Warning, this is untested.