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What is a formal grammar?

A formal grammar describes how to form strings from a language's vocabulary (or alphabet) that are valid according to the language's syntax. Linguist Noam Chomsky theorized that four different classes of formal grammars existed that could generate increasingly complex languages.

What is an example of a formal language?

Here are some examples of formal languages: L = {a} * = {a n }, where n ranges over the natural numbers and "a n " means "a" repeated n times (this is the set of words consisting only of the symbol "a"); the set of syntactically correct programs in a given programming language (the syntax of which is usually defined by a context-free grammar );

What is a formal language theory 100?

FORMAL LANGUAGE THEORY 100 (6.9) S b S a S b S a S a S b Let’s consider a somewhat harder case: a language where strings begin with an a, end with a b, with any number of intervening instances of c, e.g. {ab,acb,accb,...}. This can be described using all three grammar types.

What is a grammar in linguistics?

A grammar is a way to characterize a language L, a way to list out which strings of ??are in Land which are not. If Lis ?nite, we could simply list 94 CHAPTER 6. FORMAL LANGUAGE THEORY 95 the strings, but languages by de?nition need not be ?nite. In fact, all of the languages we are interested in are in?nite.