我对代码一窍不通，想请教一下高手，谢谢！
我想在首页加2对对联广告，加一对可以正常显示，但加两对却只显示一对对联广告
我要如何加才可以正常显示上下两对呢？谢谢！

<script src="duilian1.js"></SCRIPT>
<script src="duilian2.js"></SCRIPT>

function initEcAd() {
document.all.AdLayer1.style.posTop = -200;
document.all.AdLayer1.style.visibility = 'visible'
document.all.AdLayer2.style.posTop = -200;
document.all.AdLayer2.style.visibility = 'visible'
MoveLeftLayer('AdLayer1');
MoveRightLayer('AdLayer2');
}
function MoveLeftLayer(layerName) {
var x = 5;
var y = 165 ;
var diff = (document.body.scrollTop + y - document.all.AdLayer1.style.posTop)*.40;
var y = document.body.scrollTop + y - diff;
eval("document.all." + layerName + ".style.posTop = y");
eval("document.all." + layerName + ".style.posLeft = x");
setTimeout("MoveLeftLayer('AdLayer1');", 20);
}
function MoveRightLayer(layerName) {
var x = 5;
var y = 165;
var diff = (document.body.scrollTop + y - document.all.AdLayer2.style.posTop)*.40;
var y = document.body.scrollTop + y - diff;
eval("document.all." + layerName + ".style.posTop = y");
eval("document.all." + layerName + ".style.posRight = x");
setTimeout("MoveRightLayer('AdLayer2');", 20);
}
document.write("<div id=AdLayer1 style='position: absolute;visibility:hidden;z-index:1'><a href=http://www.17771.com/bbs/index.asp?boardid=179 target=_blank ><img src=guanggao/20062121222743700.jpg border=0></a></div>"
+"<div id=AdLayer2 style='position: absolute;visibility:hidden;z-index:1'><a href=http://www.17771.com/bbs/index.asp?boardid=23 target=_blank ><img src=guanggao/9870970000707.jpg border=0></a></div>");
initEcAd()

<script src="duilian.js"></SCRIPT>
首页调用是这样的

我是想再增加一对对联广告，我要怎么做呢？谢谢！

要怎么调用呢？