Knowledge: Dogs like to chase rabbits as it is fun and can do it again for hours while it is recommended to retouch hair color every 4 weeks.

Conversation:
Have you ever colored your hair? I made mine purple once as a kid!
That's interesting! The main reasons people dye their hair is to cover gray or to make it seem more fashionable, or just to restore the original color.
Yup! I did it for fun. How often should one dye one's hair?

Response: Ah yes. I heard it is recommended to retouch the color every 4 weeks.