"use strict";
function Person(age) {
	if (age) {
		this.age = age;
	}
}
Person.prototype.getAge = function () {
	return this.age;
};

function Student(age, grade) {
	Person.call(this, age);
	this.grade = grade;
}
Student.prototype = new Person();
Student.prototype.getGrade = function () {
	return this.grade;
};

var s = new Student(24, 5.75);
//var age = s.

//delete s.age;
//s.getAge = function() { return {foo:"bar"}; };
//s.
//s.getAge().