<?php
    ini_set('display_errors', 1);
    ini_set('display_startup_errors', 1);
    error_reporting(E_ALL);

    class Main
    {
        // Parameters
        protected $first_name;
        protected $middle_name;
        protected $last_name;

        public function first_name($first_name)
        {
            $this->first_name = $first_name;
            return $this;
        }

        public function middle_name($middle_name)
        {
            $this->middle_name = $middle_name;
            return $this;
        }

        public function last_name($last_name)
        {
            $this->last_name = $last_name;
            return $this;
        }
    }

    class FirstName extends Main
    {
        public function display_first_name()
        {
            echo $this->first_name;
        }
    }

    class MiddleName extends FirstName
    {
        public function display_middle_name()
        {
            echo $this->middle_name;
        }
    }

    class LastName extends MiddleName
    {
        public function display_last_name()
        {
            echo $this->last_name;
        }
    }

    class FullName extends LastName
    {
        public function generate()
        {
            $this->display_first_name();
            $this->display_middle_name();
            $this->display_last_name();
        }
    }

    $o = new FullName();
    $o->first_name('Ken Dan')->middle_name('Sunico')->last_name('Tinio')->generate();

    ?>

class Main
class FirstName extends Main
class MiddleName extends Main
class LastName extends Main
class FullName extends Main

is it possible to make my classes like this?