function SetID(name,x)
{
document.getElementById(name).setAttribute('id','MatarFalse');
x.setAttribute('id',name);
}
function PutImg(name,x,y)
{
document.getElementById(name+""+y).src = x;
}
<!--
function OpenWindow(mywindow)
{
if (mywindow.indexOf("sound")<0)
window.open(mywindow,"_blank",'width=700,height =600,directories=no,location=no,top=250,left=250,menubar=no,scrollbars=yes,status=no,toolbar=no,resizable=no');
else
indow.open(mywindow,"_blank",'width=700,height =600,directories=no,location=no,top=250,left=250,menubar=no,scrollbars=yes,status=no,toolbar=no,resizable=no');
}

$(document).ready(function() {
$('.MainNews_d1').show();
$('#news_tab>ul>li').click(function(){
$('.MainNews_d1').hide();
$('.MainNews_d2').hide();
$('.MainNews_d3').hide();
$('.MainNews_d4').hide();
$('.MainNews_d'+$(this).attr('MainNews')).show();
});
});