using System;

namespace Abstract classes

{

public class program

{

public static Void Main(String[]args)

{

Catcat=newCat();

Console.writeline(cat.describe());

Console.Read();

}

}

abstract class.FourleggedAnimal

{

public virtual String Describe()

{

return"This animal has four legs";

}

}

class Cat FourleggedAnimal

{

public over ride String describe

{

String result=base.Describe();

result+="

​

​