array of arrays

[Anon]

I'm trying to figure out how to fill an array with arrays inside a loop.

$mainArray = array();

now I wish to fill this array with arrays inside a loop. Something like:

for($i=0;$i<sizeof($fillArray);$i++)
{
$mainArray = array($fillArray[$i], $extraArray[$i],123,44);
}

So in the end $mainArray would print something like:

fillArray1,extraArray1,123,44
fillArray2,extraArray2,123,44
fillArray3,extraArray3,123,44

Any input would be most appreciated.
Thanks