<?php
$sym_rx = "~(?:([^-'\"()*,.:…;?`\s]+)|([-'\"()*,.:…;?`]))(\s)*~u";
$str = "'this' is Mary! (a dog - not a human)";
$ins = !empty($m[2]) ?
$m[2] . "\\SYM" : $m[1] . "\\not SYM"; return !empty($m[3]) ?
$ins . $m[3] : $ins . " "; }, $str);
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