class Vehicle  // base class (parent) 
            {
              public string brand = "Ford";  // Vehicle field
              public void honk()             // Vehicle method 
              {                    
                Console.WriteLine("Tuut, tuut!");
              }
            }
            
            class Car : Vehicle  // derived class (child)
            {
              public string modelName = "Mustang";  // Car field
            }
            
            class Program
            {
              static void Main(string[] args)
              {
                // Create a myCar object
                Car myCar = new Car();
            
                // Call the honk() method (From the Vehicle class) on the myCar object
                myCar.honk();
            
                // Display the value of the brand field (from the Vehicle class) and the value of the modelName from the Car class
                Console.WriteLine(myCar.brand + " " + myCar.modelName);
              }
            }
            
 
            

sealed class Vehicle 
            {
              ...
            }
            
            class Car : Vehicle 
            {
              ...
            }