Welcome to the English language
Have a tour with us, dear,
There are every kinds of rules here
Best of luck not getting lost in this maze.

A person who plays a piano is a pianist
But mind you, a person who races isn't a racist,
Yes a person who dances is a dancer
Just like the person who "docs" is a doctor.

"Police police police" yes you heard it right
This sentence is fully alright,
A built building is still a...