How to implement Interface Methods Partially

Here is the way to implement interface methods partially. To achieve this we need to use Abstract methods in derived class.

Interface IExample
{
      void Display1();
      void Display2();
      void Display3();
}
public abstract class Cls1 : IExample
{
      public void Display1()
      {
            throw new NotImplementedException();
      }
      public abstract void Display2();
      public abstract void Display3();
}