<?php
function replaceSpace($metin)
{
$metin = preg_replace("/s+/", " ", $metin);
$metin = trim($metin);
return $metin;
}

$kelime2=replaceSpace($metin);

if ($kelime2==1){
$sonuc = xx;
}else{
$sonuc= yy;
}

echo $sonuc;
?>