$re = '/\s1[A-Za-z]/m';
$str = '-ABC046Y 1SMITH/FREDMR
.L/JCD5CQ
.R/TKNE HK1 6002300348396/1-SMITH/FREDMR
.R/SEAT HK1 9F
.R/FQTV AB 60042576-1SMITH/FREDMR 1DOE/JANEMISS
.L/JC93QW
.R/TKNE HK1 6002300219029/2-1DOE/JANEEMISS
.R/SEAT HK1 8A
.R/CHKD HK1 011-1DOE/JANEMISS 1PRESLEY/ELVISMR-A2 ';
preg_match_all($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