用javascript如何实现? 如下所示，显示隐藏包括前面的提示字样，谢谢
1<input name="a" type="radio" value="1"/>
a
提示:
1<select name="b">
2<option value="1">1</option>
3<option value="2">2</option>
4</select>
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1<input name="a" onclick="document.all('b').style.display='none'" type="radio" value="1"/>
a
1<input name="a" onclick="document.all('b').style.display=''" type="radio" value="2"/>
b
提示:
1<select name="b">
2<option value="1">1</option>
3<option value="2">2</option>
4</select>
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1<form name="form1">
2<input name="a" onclick="document.form1.b.style.display=(this.checked)?'none':''" type="checkbox" value="1"/>a
3提示:<select name="b">
4<option value="1">1</option>
5<option value="2">2</option>
6</select>
7</form>
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1<html>
2<head>
3<meta content="text/html; charset=utf-8" http-equiv="Content-Type"/>
4<title>无标题文档</title>
5</head>
6<body>
7<input id="a" name="a" onclick="form1.style.display='none'" type="radio" value="1"/><label for="a">a</label>
8<input id="b" name="a" onclick="form1.style.display='inline'" type="radio" value="2"/><label for="b">b</label>
9<form id="form1" style="display:none">
10提示:<select name="b">
11<option value="1">1</option>
12<option value="2">2</option>
13</select>
14</form>
15</body>
16</html>