using System;

using System.Windows.Input;

​

public class Program

{

    public static void Main()

    {   

        SerVivo edu = new homem();

        edu.respirar();

        SerVivo ringo = new peixe();

        ringo.respirar();

    }

}

​

public class SerVivo

{

        public virtual void respirar(){ }

        public virtual void locomover(){}

}

public class homem : SerVivo

{

    public override void respirar(){

        Console.WriteLine("respirar ar");

    }

}

​

public class peixe : SerVivo{

​

    public override void respirar(){

        Console.WriteLine("respirar agua ");

    }

}