Neutral language?
No one develops intellectually without knowing how to speak and produce elaborate thoughts. Without vocabulary and with incorrect grammar, the scope of thought is limited; after all, if a person doesn't even know the meaning of words, how can they elaborate a thought?
Anyone who has read George Orwell's 1984 knows that changing words and their meaning can have an overwhelming impact on the human mind.
They want you speaking incorrectly, limited by your own thinking.