[Example: The example
using System;
class A
{
public virtual void F() {
Console.WriteLine("A.F");
}
public virtual void G() {
Console.WriteLine("A.G");
}
}
class B: A
{
sealed override public void F() {
Console.WriteLine("B.F");
}
override public void G() {
Console.WriteLine("B.G");
}
}
class C: B
{
override public void G() {
Console.WriteLine("C.G");
}
}
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]