When an instance method declaration includes a sealed modifier, that method is said to be a sealed method. A sealed method overrides an inherited virtual method with the same signature. An override method can also be marked with the sealed modifier. Use of this modifier prevents a derived class from further overriding the method. [Example: The example the class B provides two override methods: an F method that has the sealed modifier and a G method that does not. B's use of the sealed modifier prevents C from further overriding F. end example]