$re = '/([a-zA-Z]\.){2}([2-9][1-9][0-9]{2}|20([2-9][0-9]|19))@uts\.edu\.co/m';
$str = 'j.g.2019@uts.edu.co';
preg_match_all($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