$re = '`\b([a][\W_]*?)+([p][\W_]*?)+([p][\W_]*?)+([l][\W_]*?)+([e][\W_]*?)+(([\W_]*)([a][\W_]*?)+([n][\W_]*?)+([d][\W_]*?)+)?(([\W_]*)([l][\W_]*?)+([e][\W_]*?)+([m][\W_]*?)+([o][\W_]*?)+([n][\W_]*?)+)?\b`im';
$str = 'a pple and lemon
apple lemon
apple and
apple
apple testing today';
preg_match_all($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