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<title>Jså¤æä¸ææ¡</title>
<script>
function ss(){
var slt=document.getElementById("aa");
if(slt.value==""){
alert("请éæ©ä¸ä¸ªé¡¹ç®");
return false;
}
return true;
}
</script>
<form method=post onsubmit=" return ss()">
<select id="aa">
<option value="">请éæ©</option>
<option value="1s">ä¸</option>
<option value="2u">äº</option>
</select>
<input type=submit value="æ交">
</form>
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