<select name="id_auto" id="id_auto">
<option value="Выберите марку...">Выберите марку...</option>
';
                
                $query = mysql_query("SELECT * FROM auto");
                $answer = mysql_fetch_assoc($query);
                
                do {
                    echo '<option value="'.$answer["id_auto"].'">'.$answer["name_eng"].'</option>';
                }
                while ($answer = mysql_fetch_assoc($query));
                



echo '</select>

$(document).ready(function() {
    
   $("select#id_auto").change(function () {
    
    var opt = this.value;
    
    $.post("ajaxmodel.php", { id_auto : opt }, function(data){$("select#name_model").html(data);});
    
  });
 });

if (($_POST['id_auto'] != 'Выберите марку...')) {

$modellist = '';

$id_auto = $_POST['id_auto'];

$query = mysql_query("SELECT model.name_model, model.id_model FROM model LEFT JOIN communication ON (model.id_model = communication.id_model) WHERE communication.id_auto = '$id_auto'");
$answer = mysql_fetch_assoc($query);

do {
    
    $arraym[$answer['id_model']] = $answer['name_model'];

}
while ($answer = mysql_fetch_assoc($query));


$arraym = array_unique($arraym);

foreach ($arraym as $key => $val) {
    
    $modellist .= '<option value="'.$key.'">'.$val.'</option>';
    
}

$modellist = '<option>Выберите модель...</option>'.$modellist;

echo $modellist;

}

$result = mysql_query($query);

$prt=mysql_query($query);

ENCTYPE=multipart/form-data 

echo ("<select name=name>");

value="'.$par['id'].'"

$par = mysql_fetch_assoc($prt)