how can I use an if else statement?

<?php if ($row_rsDetail['BTW Tarief'] > 0) { // Adv Conditional Region ?>
<p class="prijs"><?php echo number_format($row_rsDetail['VerkPrijs'],2,',','.'); ?> BTW Inbegrepen</p>

-->ELSE<---

<?php } // $row_rsDetail['BTW Tarief'] > 0 ?>
<span class="prijs"><?php echo number_format($row_rsDetail['VerkPrijs'],2,',','.'); ?> ALL IN