I know that private inheritance is supported in C++ and only public inheritance is supported in C#. I also came across an article which says that private inheritance usually defines a HAS-A relationship and kind of an aggregation relationship between the classes.

EDIT: C++ code for private inheritance: The "Car has-a Engine" relationship can also be expressed using private inheritance:

class Car : private Engine {    // Car has-a Engine
 public:
   Car() : Engine(8) { }         // Initializes this Car with 8 cylinders
   using Engine::start;          // Start this Car by starting its Engine
 };

Now, Is there a way to create a HAS-A relationship between C# classes which is one of the thing that I would like to know - HOW?

Another curious question is why doesn't C# support the private (and also protected) inheritance ? - Is not supporting multiple implementation inheritance a valid reason or any other?

Is private (and protected) inheritance planned for future versions of C#?

Will supporting the private (and protected) inheritance in C# make it a better and widely used language?