<!DOCTYPE html>
<html>
<body>
<?php
// Parent class
abstract class Car {
public $name;
public function __construct($name) {
$this->name = $name;
}
abstract public function intro() : string;
}
// Child classes
class Audi extends Car {
public function intro() : string {
return "Choose German quality! I'm an $this->name!";
}
}
class Volvo extends Car {
public function intro() : string {
return "Proud to be Swedish! I'm a $this->name!";
}
}
