请帮忙看看为什么下拉无效，谢谢
<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>下拉菜单</title> <link href="http://cdn.bootcss.com/bootstrap/3.2.0/css/bootstrap.css" rel="stylesheet"></head> <body> <div class="dropdown"> <button class="btn btn-default dropdown-toggle" type="button" id="dropdownMenu2" data-toggle="dropdown"> 下拉菜单 <span class="caret"></span> </button> <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu2"> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">下拉菜单项</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">下拉菜单项</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">下拉菜单项</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">下拉菜单项</a></li> </ul> </div> <div class="dropdown"> <button class="btn btn-info dropdown-toggle" type="button" id="dropdownMenu3" data-toggle="dropdown"> 选择你喜欢的水果 <span class="caret"></span> </button> <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu3"> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">苹果</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">香蕉</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">梨</a></li> <li role="presentation"><a role="menuitem" tabindex="-1" href="#">桃</a></li> </ul> </div> <script src="http://libs.baidu.com/jquery/1.9.0/jquery.js"></script> <script src="http://cdn.bootcss.com/bootstrap/3.2.0/js/bootstrap.js"></script></body> </html>
除了id 不能一样 其他的和上面的一个一样就行了
哈哈 英语没学好