LOL I remeber my english exam, my teacher actually was dissapointed in me getting second highest possible grade insted of the highest possible.
either way to answer OP's question, Korean's don't practice english. Not at all. They are not exposed to it, they do not wanna talk it. Everything in korean tv/media is korean.. they get their movies with korean voice-overs.
when they use the internet they go on korean sites.
europeans (most of them), does not have their tv shows and movies dont voice-over, I think it's only France, Germany and Italy that gets near 100% of their media content translated or voice-over.
For me, my half sister got a english boyfriend when i was 4 years old so I was forced to learn, but also wanted to learn. I wanted to be able to communicate with him!, also I played diablo 1 from when i was 5 or 6 with my elder brother. Naturally we gathered the new terms to us like a sponge.
I'am very confident in my english skills.