class Student
  attr_accessor :name, :age, :classes
  def initialize(name, age)
    @name     =     name
    @age      =     age
    @classes  =     Classes.new()
  end

  class Classes
    attr_accessor :name, :time, :credits

    def initialize()
      @credits = 4
    end

  end
end

mkc = Student.new("MKC", "21")
mkc.classes.name    = "Ruby101"
mkc.classes.time  =   "3 hours"

puts "name: "     +    mkc.name.to_s
puts "age: "     +    mkc.age.to_s
puts "classes: {" +
                    "\n\t\t\t" + "Class.Name: " + mkc.classes.name.to_s     +
                    "\n\t\t\t" + "Class.Time: " + mkc.classes.time.to_s     +
                    "\n\t\t\t" + "Class.Credits: " + mkc.classes.credits.to_s  +
            "\n}"