$re = '/,\d{2}\,(.*),\"\d{4}-\d{2}-\d{2}\w\d{2}:\d{2}:\d{2}-\d{2}:\d{2}\",\"\w{3}"/m';
$str = '"123","456",,17,"hello," how are you this, fine, highly caffienated morning,","2018-05-29T18:58:10-05:00","XYZ",
"345","737",,16,"Heading to a "meeting", unprepared while trying to be "awake","2018-05-29T18:58:10-05:00","ACD",';
preg_match_all($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