getMenu=function(para){
	var subNav=document.getElementById("sub_nav")
	switch(para){
		case 0:
			subNav.innerHTML="<ul><li><a href=\"summary.asp?c=0\">走进科协</a></li><li><a href=\"summary.asp?c=1\">学会之窗</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="140px";
			break;
		case 1:
			subNav.innerHTML="<ul><li><a href=\"catalog.asp?c=0&cg=1\">科普动态</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="230px";
			break;
		case 2:
			subNav.innerHTML="<ul><li><a href=\"catalog.asp?c=1&cg=1\">物质结构</a></li><li><a href=\"catalog.asp?c=1&cg=2\">数理逻辑</a></li><li><a href=\"catalog.asp?c=1&cg=3\">生命起源</a></li><li><a href=\"catalog.asp?c=1&cg=4\">宇宙空间</a></li><li><a href=\"catalog.asp?c=1&cg=5\">生存环境</a></li><li><a href=\"catalog.asp?c=1&cg=6\">智能奥秘</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="300px";
			break;
		case 3:
			subNav.innerHTML="<ul><li><a href=\"catalog.asp?c=2&cg=1\">绿色学校</a></li><li><a href=\"catalog.asp?c=2&cg=2\">水</a></li><li><a href=\"catalog.asp?c=2&cg=3\">土壤</a></li><li><a href=\"catalog.asp?c=2&cg=4\">大气</a></li><li><a href=\"catalog.asp?c=2&cg=5\">环保</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="260px";
			break;
		case 4:
			subNav.innerHTML="<ul><li><a href=\"catalog.asp?c=3&cg=1\">校园科普</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="430px";
			break;
		case 5:
			subNav.innerHTML="<ul><li><a href=\"catalog.asp?c=4&cg=1\">科普图作</a></li><li><a href=\"catalog.asp?c=4&cg=2\">科普知识竞赛</a></li><li><a href=\"catalog.asp?c=4&cg=3\">科普征文</a></li><li><a href=\"catalog.asp?c=4&cg=4\">科学实验</a></li><li><a href=\"catalog.asp?c=4&cg=5\">科普旅游</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="330px";
			break;
		case 6:
			subNav.innerHTML="";
			break;
		case 7:
			subNav.innerHTML="<ul><li><a href=\"download.asp?t=0\">资源交流</a></li><li><a href=\"download.asp?t=1\">下载中心</a></li></ul>";
			subNav.getElementsByTagName("ul")[0].style.marginLeft="700px";
			break;
		default:break;
	}
}