public class Father
    {
        public void Write() {
            Console.WriteLine("父");
        }
    }

    public class Mother
    {
        public virtual void Write()
        {
            Console.WriteLine("母");
        }
    }

    public class Boy : Father
    {
        public new void Write()
        {
            Console.WriteLine("子");
        }
    }

    public class Girl : Mother
    {
        public override void Write()
        {
            Console.WriteLine("女");
        }
    }

static void Main(string[] args)
        {
            Father father = new Boy();
            father.Write();

            Boy boy = new Boy();
            boy.Write();

            Mother mother = new Mother();
            mother.Write();

            Girl girl = new Girl();
            girl.Write();

            Console.ReadLine();
        }

public class Boy : Father
    {
        public new void Write()
        {
            base.Write();
            Console.WriteLine("子");
        }
    }

    public class Girl : Mother
    {
        public override void Write()
        {
            base.Write();
            Console.WriteLine("女");
        }
    }