I found a task where you need to transform context free grammar to normal form. I'm a High Shcool student at this moment. But my Brother learning this at the university. He don't have much time to explan this, this is why I'm writting this question.
This is the task description: A chainless G grammar equivalent to G' grammar, all symbols of which can be used.
And the task is:
G : S → BC | DB A → BD B → b | D C → CD | BC D → bC | a | bB
If anybody can help me, please write a comment. Thanks :)