var oMarquee4 = document.getElementById("mq4"); //滚动对象
var iLineHeight4 = 38; //单行高度，像素 
var iLineCount4 = 2; //实际行数 
var iScrollAmount4 = 1; //每次滚动高度，像素 

function run4() { 
oMarquee4.scrollTop += iScrollAmount4; 
if ( oMarquee4.scrollTop == iLineCount4 * iLineHeight4 ) 
oMarquee4.scrollTop = 0;
if ( oMarquee4.scrollTop % iLineHeight4 == 0 ) { 
window.setTimeout( "run4()", 8000 ); 
} else { 
window.setTimeout( "run4()", 60 ); 
} 
} 

oMarquee4.innerHTML += oMarquee4.innerHTML; 
window.setTimeout( "run4()", 8000 );