【【【有个问题需要大家的帮忙！！！！】】】

Question

document.getElementById("sp_"+i).innerHTML=i;

Answer 1

<span id="sp_i">&nbsp;</span>
<script>
var i=0;
function $()
{
  i++
  document.getElementById("sp_i").innerHTML=i;
  setTimeout("$()",1000);
}
$()
</script>

Answer 2

<input type=text id=t value="0">
<SCRIPT LANGUAGE="JavaScript">
<!--
function a() {
document.getElementById('t').value++;
setTimeout("a()",500);
}
a();
//-->
</SCRIPT>

Answer 3

<span id="sp_i"></span>
<script>
i = 0;
setInterval("document.getElementById('sp_i').innerHTML=i++", 100);
</script>