class Item {
    public $name;
    public function __constructor($name) {
        $this->name = $name;
    }
    public function ShowDate() { ... };
}

class thing extends Item{
    public $dimension;
    public function __constructor ($name, $dimension) {
        parent::$name;
$this-> $dimension = $ dimension;
    }
}

class food extends Item{
    public $place;
    public function __constructor($name, $place) {
        parent::$name;
        $this->place = $place;
    }
}