$re = '/\b(Fat(\W?|\W?\b.*\b)(Bike|Trike))\b/mi';
$str = 'My father\'s fat bike is a fat tyre bike.
My father\'s fat-bike is a fat tyre bike.
My father\'s Fat Tyre Electric Bike.
My father\'s fat-bike.
My father\'s fat, bike.
My father\'s fat, tyre, bike.
My father\'s fat, tyre, electric-bike.
My father\'s fat, tyre, electric bike.
My father\'s fat, tyre. Electric bike.
My father\'s fat-tyre, electric bike.
My father\'s fat, tyre, electric Trike.
#FatBike
#Fat-Bike
#Fat-Tyre-Bike
#FatTrike
My father\'s fat motorbike.
My father\'s fat tyre motorbike.
My father\'s lefat tyre electric bike.
My father\'s fat tyre electric biker.
My father\'s fat1 tyre, electric bike.
My father\'s fatt tyre, electric bike.
#FatTyreBike
';
preg_match_all($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