$re = '/^[\ \t]*(\S?(?:.*\S)?)?[\ \t]*$/mi';
$str = 'The door swung open to reveal pink giraffes and red elephants.
He stomped on his fruit loops and thus became a cereal killer.
Lightning Paradise was the local hangout joint where the .
a
sd
a
He didn’t want to go to the dentist, yet he went anyway.
He decided to count all the sand on the beach as a hobby.
* Situps are a terrible way to end your day.
The random sentence generator generated a random sentence about a random sentence.
As time wore on, .
The beach was crowded with snow leopards.
She was too short to see over the fence.
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php