$re = '/(?:\(\d+\)|\d+(?:\s*-\s*\d+)?)(?:\s+(?:\(\d+\)|\d+(?:\s*-\s*\d+)?))*$/m';
$str = 'Modernization and improvement (note 9) 260 (180) 640 - 155
Modernization and improvement (note 9) 155
Modernization and improvement (note 9) 260 (180)
Modernization and improvement (note 9) 640 - 155';
preg_match_all($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