$re = '/^(_{2}\([\'\"]{1})([a-zA-Z1-9\s%\_\'\.\,(\"\))*\(\=\>\$\-\!]*[(\){1,3})*(\'\)*)(\){1,3})*(\"\))*]+)/';
$str = '__(\'Register and apply for %job_title%\', array(\'%job_title%\' => $job->getTitle()));
__("Invalid File".$something." Extension");
__("Employers9");
_sometime
__(\'Please read the Privacy Policy and tick $the %ceva%box to say you have done so.!\')
__(\'Register and apply for %job_title%\', array(\'%job_title%\' => $job->getTitle()))
';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($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