Set two iterators and print everything between them. So something like this:
<?
$str = "How are you";
$words = explode(" ",$str);
$num_words = count($words);
for ($i = 0; $i < $num_words; $i++) {
for ($j = $i; $j < $num_words; $j++) {
for ($k = $i; $k <= $j; $k++) {
print $words[$k] . " ";
}
print "\n";
}
}
?>
Output
How
How are
How are you
are
are you
you