Last Name: " . $last_name . "
"; echo "First Name: " . $first_name . "
"; echo "Age: " . ($age !== null ? $age : 'Not provided') . "
"; echo "Gender: " . $gender . "
"; } else { // Handle missing required fields echo "Error: First name and last name are required.
"; } } else { echo "No form was submitted.
"; } ?>