js給value動態賦值

//動態改變少數民族的值
	function checkSelect(){
		var ontion = document.getElementById("nations").value;
		//alert("少數民族的值爲："+ontion);
		var on = document.getElementById("na2").value=ontion;
		//alert("賦值爲："+on);
		
	}

 <input id="na" type="radio" name="ysBaseInfo.nation" value="1" />漢族
        <input id="na2" type="radio" name="ysBaseInfo.nation" value="0" />少數民族
      	<select id="nations" οnchange="checkSelect();" class="input_select1">
      		<option></option>
      		<option value="2">蒙古族</option>
      		<option value="3">回族</option>
      		<option value="4">藏族</option>
      		<option value="5">維吾爾族</option>
      		<option value="6">苗族</option>
      		<option value="7">彝族</option>
      		<option value="8">壯族</option>
	</select>