Clsss Inheritance:

 <?php

// Parent class

class Vehicle {

    public $brand;

    public $model;

    

    // Constructor

    public function __construct($brand, $model) {

        $this->brand = $brand;

        $this->model = $model;

    }

    // Method in parent class

    public function start() {

        echo "The vehicle is starting.\n";

    }

}

// Child class inheriting from the Vehicle class

class Car extends Vehicle {

    public $doors;

    

    // Constructor in child class

    public function __construct($brand, $model, $doors) {

        // Call parent class constructor to initialize properties

        parent::__construct($brand, $model);

        $this->doors = $doors;

    }

    // Method in child class

    public function honk() {

        echo "The car is honking.\n";

    }

    // Overriding the parent method

    public function start() {

        echo "The car is starting.\n";

    }

}

// Creating an instance of the Car class

$car = new Car("Toyota", "Corolla", 4);

// Accessing inherited properties

echo "Brand: " . $car->brand . "\n";  // Outputs: Brand: Toyota

echo "Model: " . $car->model . "\n";  // Outputs: Model: Corolla

echo "Doors: " . $car->doors . "\n";  // Outputs: Doors: 4

// Calling methods

$car->start();  // Outputs: The car is starting.

$car->honk();   // Outputs: The car is honking.

?>