Wat is hier fout?

<?php
if(IsSet($_POST['submit']))
   {
   mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']'." LIMIT 1") or die mysql_error());
   echo "De link is met succes gewijzigd";
   }
  if($_POST['wijzig']) //LINE 78
   {
   $query = mysql_query("SELECT * FROM links");
   $id = $_POST['id'] -1;
?>
<form method="POST">
<table width="100%" cellspacing="0" cellpadding="1" border="0">
 <tr>
  <td>Naam link:</td><td><input type="text" name="naam" value="<? echo mysql_result($query, $id, "naam"); ?>"></td>
 </tr>
 <tr>
  <td>Link:</td><td><input type="text" name="link" value="<? echo mysql_result($query, $id, "link"); ?>"></td>
 </tr>
 <tr>
  <td>Bericht:</td><td><textarea rows="8" cols="40" name="beschrijving" value="beschrijving"><? echo mysql_result($query, $id, "beschrijving"); ?></textarea></td>
 </tr>
 <tr>
  <td colspan="2" align="center"><input type="submit" name="submit" value="Bewerk"> &nbsp;<input type="submit" value="Terug" OnClick="javascript:history.back()"></td>
 </tr>
</table>
</form>
<?php
} else {
?>
<form method="POST">
<table width="100%" cellspacing="0" cellpadding="1" border="0">
 <tr><td width="5%"><b>#</b></td><td width="45%"><b>Naam link:</b></td><td width="50%"><b>Link:</b></td></tr>
<?php
$query = mysql_query("SELECT * FROM links ORDER BY naam ASC");

while($wijzig = mysql_fetch_object($query))
 {
 echo "<tr><td><input type=\"radio\" name=\"id\" value=\"".$wijzig->id."\"></td><td>$wijzig->naam</td><td>$wijzig->link</td></tr>";
 }
?>
<tr><td colspan="3"><input type="submit" value="Wijzig" name="wijzig"></td></tr>
</table>
</form>
<?php
}
}
?>

<?php
if(IsSet($_POST['submit']))
   {
   mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']'." LIMIT 1") or die mysql_error());
   echo "De link is met succes gewijzigd";
   }
  if($_POST['wijzig']) //LINE 78
   {
   $query = mysql_query("SELECT * FROM links");
   $id = $_POST['id'] -1;
?>
<form method="POST">
<table width="100%" cellspacing="0" cellpadding="1" border="0">
 <tr>
  <td>Naam link:</td><td><input type="text" name="naam" value="<? echo mysql_result($query, $id, "naam"); ?>"></td>
 </tr>
 <tr>
  <td>Link:</td><td><input type="text" name="link" value="<? echo mysql_result($query, $id, "link"); ?>"></td>
 </tr>
 <tr>
  <td>Bericht:</td><td><textarea rows="8" cols="40" name="beschrijving" value="beschrijving"><? echo mysql_result($query, $id, "beschrijving"); ?></textarea></td>
 </tr>
 <tr>
  <td colspan="2" align="center"><input type="submit" name="submit" value="Bewerk"> &nbsp;<input type="submit" value="Terug" OnClick="javascript:history.back()"></td>
 </tr>
</table>
</form>
<?php
} else {
?>
<form method="POST">
<table width="100%" cellspacing="0" cellpadding="1" border="0">
 <tr><td width="5%"><b>#</b></td><td width="45%"><b>Naam link:</b></td><td width="50%"><b>Link:</b></td></tr>
<?php
$query = mysql_query("SELECT * FROM links ORDER BY naam ASC");
 
while($wijzig = mysql_fetch_object($query))
 {
 echo "<tr><td><input type=\"radio\" name=\"id\" value=\"".$wijzig->id."\"></td><td>$wijzig->naam</td><td>$wijzig->link</td></tr>";
 }
?>
<tr><td colspan="3"><input type="submit" value="Wijzig" name="wijzig"></td></tr>
</table>
</form>
<?php
}
}
?>

<?php
mysql_query("UPDATE links SET naam = '".$_POST['naam']."', link = '".$_POST['link']."', beschrijving = '".$_POST['beschrijving']."' WHERE id = '".$_POST['id']."' LIMIT 1") or die mysql_error());
?>

<?php
mysql_query("UPDATE links SET naam = '".$_POST['naam']."', link = '".$_POST['link']."', beschrijving = '".$_POST['beschrijving']."' WHERE id = '".$_POST['id']."' LIMIT 1") or die mysql_error());
?>

   mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']'." LIMIT 1") or die mysql_error());

mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']'." LIMIT 1") or die mysql_error());

   mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']"." LIMIT 1") or die mysql_error());

mysql_query("UPDATE `links` SET `naam` = '".$_POST['naam']."', `link` = '".$_POST['link']."', `beschrijving` = '".$_POST['beschrijving']."' WHERE `id` = '".$_POST['id']"." LIMIT 1") or die mysql_error());