HTML的下拉框

<select  id = "province" name = "province">
<option value = "hubei">湖北</option>
<option value = "hunan">湖南</option>
<option value = "guangdong">广东</option>
<option value = "jiangsu">江苏</option>
</select>


<select id = "city1" name = "city1">
<option value = "xf">襄樊</option>
<option value = "wh">武汉</option>
<option value = "xt">仙桃</option>
<option value = "jz">荆门</option>
</select>


<select id = "city2" name = "city2">
<option value = "cs">长沙</option>
<option value = "yy">岳阳</option>
<option value = "xt">湘潭</option>
<option value = "jm">集美</option>
</select>

<select id = "city3 name = "city3">
<option value = "gz">广州</option>
<option value = "sz">深圳</option>
<option value = "st">汕头</option>
<option value = "sw">汕尾</option>
</select>

<select id = "city4" name = "city4">
<option value = "sz">苏州</option>
<option value = "zj">镇江</option>
<option value = "nj">南京</option>
<option value = "bc">巴城</option>
</select>