I have been delving into a lot of Dr. Suess books lately, as I teach my students songs from Suessical the Musical. I'd like to use this interesting author as an example of what it means to be bold.
Dr. Suess invited his own words. The language he was taught was insufficient in the whimsical universe of his imagination, so he created what he needed - and did so boldly, without asking for permission. If you look to another to set the rules, you give yourself limitations.
What do you need to express yourself fully?
Create it. And don't ask for permission.