<?php
abstract class ParentClass {
  // Abstract method
with an argument
  abstract protected
function prefixName($name);
}

class ChildClass extends ParentClass {
  public function prefixName($name) {
   
if ($name == "John Doe") {
      $prefix = "Mr.";
   
} elseif ($name == "Jane Doe") {
      $prefix =
"Mrs.";
    } else {
     
$prefix = "";
    }
    return
"{$prefix} {$name}";
  }
}

$class = new ChildClass;
echo $class->prefixName("John
Doe");
echo "<br>";
echo $class->prefixName("Jane Doe");
?>

<?php
abstract class ParentClass {
  // Abstract method
with an argument
  abstract protected
function prefixName($name);
}

class ChildClass extends ParentClass {
 
// The child class may define optional arguments that are not in the parent's
abstract method
  public function prefixName($name, $separator = ".",
$greet = "Dear") {
   
if ($name == "John Doe") {
      $prefix = "Mr";
   
} elseif ($name == "Jane Doe") {
      $prefix =
"Mrs";
    } else {
     
$prefix = "";
    }
    return
"{$greet} {$prefix}{$separator} {$name}";
  }
}

$class = new ChildClass;
echo $class->prefixName("John
Doe");
echo "<br>";
echo $class->prefixName("Jane Doe");
?>