1. lunatic

 He is lunaic for doing such a thing. Why does he act rudely? Never call him for this meeting from now on.

2. loony

 I wouldn't have had a car accident yesterday owing to a loony car!

 I was startled all of a sudden. You should be careful when you drive.

 

It's very impressive there are many expressions that means 'crazy' 

and your Korean  words by writing in English. ^^

Enjoy your day~~! and see you^^