$re = '/(?=.{2,100}$)[^\W\d_]{2,}(?:[-\s][^\W\d_]{2,})*/m';
$str = '########################### valid names ##############################
Peter
Hans-Peter
Hector Sausage-Hausen
Alexander Groß
àáâäãåąčćęèéêëėįìíîïłńòóôöõøùúûüųūÿýżźñçčšžÀÁÂÄÃÅĄĆČĖĘÈÉÊËÌÍÎÏĮŁŃÒÓÔÖÕØÙÚÛÜŲŪŸÝŻŹÑßÇ
Martin Luther King Jr
Martin Luther King Jr.
Saäüößin
Älbert
Ülbert
Ölbert
Mo
Mathias d\'Arras
Mike O\'Neal
Peter.
Peter?
Peter!
Boby-Dick.
Boby-Dick?
Boby-Dick!
########################### not valid names ###########################
Peter123
Stev3 Smith
Steve Sm1th
Peter...
Max!"§$%&/()
Max_
M
Peter?!?
Peter(
(Peter)
';
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