function marqueeset(demo,demo1,demo2){
	demo=document.getElementById(demo);
	demo1=document.getElementById(demo1);
	demo2=document.getElementById(demo2);
	var speed=30;
	demo2.innerHTML=demo1.innerHTML; //克隆demo1为demo2
	function Marquee(){
		if(demo2.offsetTop-demo.scrollTop<=0) { //当滚动至demo1与demo2交界时
			demo.scrollTop-=demo1.offsetHeight;  //demo跳到最顶端
		}else{
			demo.scrollTop++;
		}
	}
	var MyMar=setInterval(Marquee,speed); //设置定时器
	demo.onmouseover=function() {clearInterval(MyMar);} //鼠标移上时清除定时器达到滚动停止的目的
	demo.onmouseout=function() {MyMar=setInterval(Marquee,speed);} //鼠标移开时重设定时器
}