<select name="sido" id="sido"><option value="">-시도-</option></select>

<select name="gugun" id="gugun"><option value="">-구군-</option></select>

<select name="dong" id="dong"><option value="">-동-</option></select>

<script src="sojaeji.js"></script>

<script>

//sojaeji('<?php echo $wr_1?>', '<?php echo $wr_2?>', '<?php echo $wr_3?>');

sojaeji('서울', '강남구', '신사동');

</script>