用表格来设置
<table border="1" width="200">
<tr>
<td width="100%">
<select name="sel" size="1" style="width:100%">
<option selected value="123">123</option>
</select>
</td>
</tr>
</table>
<table border="1" width="200">
<tr>
<td width="100%">
<select name="sel" size="1" style="width:100%">
<option selected value="123">123</option>
</select>
</td>
</tr>
</table>
anyway
thank u a,gal
<option value="a">a
<option value="b">b
</select>
<option value="a">a</option>
<option value="b">b</option>
</select>
hehe