<?php if($a == $b){?>
<?php
if ($a % 2 == 1):
echo "ほしい";
?>
<?php }?>
//It seems to me, that many people think that
<?php if ($a == 5): ?>
A ist gleich 5
<?php endif; ?>
//is only with alternate syntax possible, but
<?php if ($a == 5){ ?>
A ist gleich 5
<?php }; ?>
//is also possible.
//alternate syntax makes the code only clearer and easyer to read
//If you wan't to use the alternative syntax for switch statements this won't work:
<div>
<?php switch($variable): ?>
<?php case 1: ?>
<div>
Newspage
</div>
<?php break;?>
<?php case 2: ?>
</div>
Forum
<div>
<?php break;?>
<?php endswitch;?>
</div>
//Instead you have to workaround like this:
<div>
<?php switch($variable):
case 1: ?>
<div>
Newspage
</div>
<?php break;?>
<?php case 2: ?>
</div>
Forum
<div>
<?php break;?>
<?php endswitch;?>
</div>