To prove that a language is regular

To prove that a language is context-sensitive

To prove that a language is context-free

To prove that a language is not context-free

A → α A → β

A → αA | β A' → ε’

A → ε A' → αA

A → βA' A' → αA' | ε

Reordering production rules

Replacing non-terminals with terminal symbols

Replacing terminal symbols with non-terminals

Introducing new non-terminals to eliminate left recursion

A → aB

A → BC

A → BCD

All the mentioned

Backus-Naur Form

Any form

Chomsky Normal Form

Greibach Normal Form

It increases the number of production rules

It simplifies the grammar for parsing algorithms

It makes the grammar ambiguous

Each production has at most one terminal on the left-hand side

Each production is either of the form A → BC or A → a

Each production has at most one non-terminal on the right-hand side

Each production is either of the form A → aB or A → a

Both terminals and non-terminals

None of the above

Terminals

Non-terminals