$re = '/"s":\[".+",*]/';
$str = '[{"code":1,"pos":0,"row":0,"col":0,"len":3,"word":"gae","s":["gay","game","age","gee","gage"]}]';
preg_match($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