In BNF, you define a language by writing a set of definitions called rules or ______________________, each of which describing the structure of a language construct, e.g., an assignment statement.

Which of the followings is an incorrect statement about the Extended BNF (EBNF)?

		BNF has been extended in several ways to provide short-hand notations called ENBF.
		EBNF enhances the descriptive, or expressive, power of BNF in that it can express a language that cannot be expressed in BNF.
		The most common extensions of EBNF include optional parts, repetitions, and alternatives.
		An example EBNF rule is: -> {( | )}.