To account for natural languages we must therefore move up at least one level, to context-free grammars (push-down automata). The powerful new properties available are: recursiveness (a rule can ...

Automata: Abstract machines ... Context-Free Grammar: A type of formal grammar that can generate all possible strings in a given formal language, allowing for nested structures. EXPTIME-complete: ...

Apply standard conversion algorithms to process automata and grammars; Read and create proofs establishing the equivalence or non-equivalence of automata and/or grammars; Design context-free grammars ...