<?phppublic class Dog {private $name;private $color;private $breed;public function Dog($name, $color, $breed) { $this->name = $name; $this->color = $color; $this->breed = $breed;}public function getColor() { return $this->color;}public function test(Dog $dog) { $dog->color = 'Brown';}}// some examples$mydog = new Dog('Rover', 'Red', 'Labrador');// prints out 'Red'echo $mydog->getColor();$anotherdog = new Dog('', '', '');$anotherdog->test($mydog);// prints out 'Brown'echo $mydog->getColor();?>