I used to tutor english a couple of years ago to 2 Korean kids. It was really fun and I enjoyed it a lot. I taught them all kinds of slang and bad words and we would laugh the whole time and then play video games. That’s when I actually started thinking about idioms and I have to say my FAVOURITE one would be:
Three sheets to the wind.
If you don’t know, it’s what someone says to describe someone who’s acting crazy or out of control. I never really understood where this one came from, but whenever someone would say it I would always picture someone running crazily through a field with 3 bed sheets flying in the wind… and naturally I would crack up laughing. Today I learned where this idiom actually comes from.