SummarizingKeywordCombinations The following table summarizes the various valid (yes) and invalid (no) keyword combinations. Keyword Interface Abstract class Class Sealed class struct Abstract no yes no no no New yes* yes yes yes no† override no yes yes yes no‡ private no yes yes yes yes protected no yes yes yes no** public no yes yes yes yes sealed no yes yes yes no virtual no yes yes no no * An interface can extend another interface and introduce a new method with the same signautre. † A struct implicitly derives from System.Object, which contains methods that the struct can hide. ‡ A struct implicitly derives from System.Object, which contains no virtual methods. ** A struct is implicitly sealed and cannot be derived from. • If you want to continue to the next chapter Keep Visual Studio 2005 running and turn to Chapter 13. • If you want to exit Visual Studio 2005 now On the File menu, click Exit. If you see a Save dialog box, click Yes. . Summarizing Keyword Combinations The following table summarizes the various valid (yes) and invalid (no) keyword combinations. Keyword Interface