Grammar Lesson
 

My nine year old has grown fond of the word "slain" but he doesn't know the tenses. "Daddy I'm about to slain one! ... Should I slain another?" Etc.

It's too damn cute for me to correct him... he doesn't get any other words wrong that I'm aware of. Does this make me a bad dad?

Does he know how to conjugate 'to grow' and 'to know'? Because i can think of few other word with similar constructions. Even 'did' is less weird than 'grew' and 'slew'.

Pretty sure he knows all those. They may be less confusing but they're definitely more common!

Try confusing him further: "you have grain so much since last year!"

"I'm slowing monsters!"