while ( defined (my $paragraph = $enumerate->Next()) ) {

    my $words = Win32::OLE::Enum->new( $paragraph->{Range}->{Words} );

    while ( defined ( my $word = $words->Next() ) ) {

        my $font = $word->{Font};
        $font->{Bold} = 1 if $word->{Text} =~ /Perl/;
    }
}