$re = '`\bCHECKOUT[a-zA-Z_(/ ):]+\w+:\w+\s(?:[AP]M|[ap]m)\s-\s\w+:\w+\s(?:[AP]M|[ap]m)(?!.*\bDRY GOODS\b).*`m';
$str = 'CHECKOUT Senior Guest Services Manager FRONTENDMGR: 07:00 AM - 08:30 AM SGSM_BOOKKEEPING: 08:30 AM - 01:00 PM FRONTENDMGR: 01:00 PM - 04:00 PM
CHECKOUT Guest Services Manager BOOKKEEPER: 09:00 AM - 01:00 PM DRY GOODS Receiving Clerk RECEIVE: 04:30 AM - 09:00 AM
DRY GOODS Receiving Clerk RECEIVE: 04:30 AM - 09:00 AM CHECKOUT Guest Services Manager BOOKKEEPER: 09:00 AM - 01:00 PM';
preg_match_all($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