public class MyBase

{

public virtual string Meth1()

{

return "MyBase-Meth1";

}

public virtual string Meth2()

{

return "MyBase-Meth2";

}

public virtual string Meth3()

{

return "MyBase-Meth3";

}

}

class MyDerived:MyBase

{

public override string Meth1()

{

return "MyDerived-Meth1";

}

public override string Meth2()

{

return "MyDerived-Meth2";

}

public override string Meth3()

{

return "MyDerived-Meth3";

}

public static void Main()

{

MyDerived md=new MyDerived();

MyBase mb=new MyBase();

System.Console.WriteLine(mb.Meth1());

System.Console.WriteLine(mb.Meth2());

System.Console.WriteLine(mb.Meth3());

}

}